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Just a Word about Colored Pond Liners

By | General Tips

Most people have gotten used to the color black being their only choice when it comes to pond liners.  While black is not a bad color, Pond Armor for instance, offers a large selection of standard colored pond liner epoxies.  We also offer custom colors as well.

Think of the possibilities of using a different colored pond liner.  Take for example the difference in appearances between limestone and granite or shale and slate.  All of these rocks are very different in color.

Using a gray or a tan colored pond liner will enhance a partner color found in a specific rock.  This in turn can also add to the natural aesthetics of the pond over-all.  Picture in your mind what the pond would look like if the colored pond liner blended into the surrounding stone.

If you have a more formal type of pond, you may need to use very bold colored pond liner epoxy.  Colors like white or competition blue might make a statement.  By the way, competition blue is a perfect color for fresh and salt water aquariums too.

So what it all boils down to is that you might consider thinking outside of the box when trying to decide which colored pond liner to choose.  The two or three design possibilities you have in your head right now may turn into a couple dozen new ideas just by adding a little color to them.

Pond Liner Glue – Does it Really Work?

By | Rubber and Plastic Liners

I am always asked if Pond Shield epoxy can be used as a pond liner glue.  The short answer is no.  I hate to disappoint, but while there are times Pond Shield epoxy can be used in the same manner as a glue, it can not be used as a pond liner glue.

The real issue here is not that Pond Shield is not sticky enough.  It really is.  The issue is that the epoxy and the liner are from two very different families of materials, in the case of a rubber liner.

While Pond Shield sticks to PVC and ABS pipes, this does not mean that it will stick to PVC liners either.  The problem here is the difference in material flexibility.  All flexible liners are going to be on the furthest edges of the scale with is comes to flexibility.

So in essence, it amounts to two major issues, the family of materials and the flexibility.  If you want to use a pond liner glue that will have any success of working, the pond liner glue needs to cover both of those issues, being of the same family of materials and at least as flexible.

The down side of pond liner glue is that they can be tricky to get to work properly.  If you read my article Patching a Pond Liner,  you will get a better understanding of how this process works.

You should be aware that pond liner glue and patches do have their issues even if you follow the rules with repairs, so you will want to take care of them and treat them with extra care so that the patch lasts as long as possible.

When to Spray Epoxy

By | Spray in Liner Ponds

This will not be an article that is too in depth but probably helpful none the less.  In the How to Spray Epoxy article, I mentioned one “when” you should spray.  That was determined by how much epoxy it will take to spray your pond.  If you do not have enough area to cover, the rental of the equipment, the set up and clean up time and the bit of Pond Shield epoxy you will loose in the system will cost you in the end.

However, there are times when spraying even a smaller area than 8 quart and a half kits (3-gallon kit) will cover is essential or at least food for thought.  Those are areas in which the ponds surface is so rough that trying to squeegee or roll the epoxy onto them will cost you a lot more in the long run than the set up or clean up time or the loss of a little bit of epoxy.

I have seen ponds that people have told me are pretty smooth that really ended up looking like a broom finish.  These are the worst areas to try and squeegee or roll.  The reason is that surfaces like this have very accentuated peaks and valleys.  So as you squeegee 10 mils over the peaks of a surface like this that has 30 mil deep valleys, you are essentially applying 40 mils over the valley areas.  That is a serious waste of material!

So spraying an area like this would be ideal.  Also, you might consider spraying a waterfall area.  Waterfalls are sometimes difficult because of all of the uneven surfaces they have so trying to brush epoxy on before it cures in the container you’re carrying around can be a problem.  Spraying the clear Pond Shield epoxy on the majority of the surface and then touching up the nook and crannies later is a quick and effective way to accomplish the task.

How to Spray Epoxy

By | How To

There are some great reasons why you would want to spray Pond Shield epoxy rather than squeegee or roll it on.  Learning how to spray epoxy is not difficult to do either.  It takes some patience, the correct tools and an assistant.

Since you are actually building a pond, let’s assume you have the patience.  You will also have to decide if you have an area large enough to spray.  This is important because Pond Shield is not sprayed with a normal, hand held paint sprayer.  The epoxy is just too thick, even if you thin it some.

So the type of spray machine you will need is an airless rig that can most likely be rented from a local tool rental store.  Now because you will be using one of these, this is where the total area to be sprayed comes into play.  The set up and cleaning of these types of machines take some time, not to mention the machine and the hose will cause you to loose some of the Pond Shield you have purchased.

I would recommend that if you consider spraying the epoxy, that you have enough area for at least 8 quart and a half kits and then purchase a minimum of a 3-gallon kit (which equates to 8 quart and a half kits).  Any less material for a spray job and you will be wasting your time and material.

So let’s assume you have enough area to spray.  Which airless spray machine do you rent or purchase (in the case of a professional installer)?  Bigger is always better, but there are some minimum requirements for a spray machine that you have to abide by.

Operating Pressure – 3000 – 3500 working psi minimum.  This means that the machine should operate in this range.  If the machine is rated for 3000 psi maximum, you may find that the operating pis is somewhere in the 1500 psi area.  That pressure will never do.

Spray Tip – This is the part of the spray gun where the epoxy exits the machine.  If the spray tip is too small, the psi that the machine operates at will be impeded and not enough coating will exit the gun to do the job properly.  The spray tip should be a minimum of .023 to .027.  I personally try and find the bigger tips work better.  The more volume you can move, the easier it is to cover your project.

Fluid Hose – Typically there are tow types of hose, both measured in inside diameter, 3/8” and 1/2.  Again, the need is for volume, then try and get the large inside diameter hose.

Gas or Electric – Either type will work fine.  I do find that gas machines tend to be larger in terms of the operating pressure and such but you should check the machine specifications before you rent.

So now we know there is enough area to be sprayed and we have picked out the proper machine.  What is the assistant for?  Well when it comes to spraying epoxy and you are going to be the trigger man, you will want to continuously spray without stopping.  Being an exothermic material the epoxy will want to heat up as it cures and airless spray machines have a tendency to further this heating process as the fluid lines are charged.  So with that said, you will probably not have enough time to stop spraying and mix additional material yourself, nor will you have the time to change from epoxy to solvent to clean the machine when you are finished.

Your assistant should be well versed in the timing for mixing new epoxy and having it ready at the same time you need it.  You, as the person spraying the epoxy should not be waiting for your assistant to finish mixing materials and likewise your assistant should not be waiting for you to finish spraying the epoxy.  This timing is essential for sake of the machine.  You do not want the epoxy hardening up in the machine while you wait, nor do you want to epoxy starting to cure in a bucket while the assistant waits for you.

Now that all of the logistics are handled, let’s talk about the actual spraying process.  Spraying is not that difficult and you can quickly get used to the manner in which you should do it.  The first thing you want to do is wear a respirator.  Yes, Pond Shield epoxy is non toxic, but the small coating particulates that will be floating in the air are not something you will want in your lungs, so protect yourself.  Any good painter will tell you this too.

You may also consider safety glasses as well because of the same reason.  There is bound to be some bounce back of epoxy from the surface being sprayed and you do not want that in your eyes either.

The first thing you should do is purge or pre-clean the spray machine of contaminants.  This is done by spraying denatured alcohol through the machine for a few minutes.  This denatured alcohol can be sprayed into a separate bucket and used later for cleaning the machine. Acetone will work as well, but it is always best to check with the owner’s manual of the machine for proper cleaning methods.

Now that the system has been purged, your assistant will load a fresh batch of Pond Shield epoxy.  Thinning the epoxy is crucial to the operation of the machine, so you may wish to speak to a support technician at Pond Armor who will be happy to help you with a proper recipe before starting.  Be sure to have all of your spray machine specifications handy before the call.

Initially the material that you spray will be mostly denatured alcohol, so purge this off with the properly mixed Pond Shield epoxy into a different bucket than the one you just pre-cleaned the machine with.  As soon as you see good epoxy coming from the machine you can move to the work area and begin.

The spray tip on the gun will either have a flat fan pattern or a round funnel pattern.  This will not make much of a difference for the type of spray job you are doing but will tend to designate how close you hold the spray gun to the surface of the pond.

Hold the spray gun somewhere between 12 and 18 inches to start.  This distance will vary depending on the type of pattern the gun sprays.  Typically, the funnel type of pattern feels like a lot more epoxy is being delivered at one time, so you will probably end up holding the spray gun further away and you perform a stroke.

The other thing that will affect this distance is the volume of epoxy being released from the machine.  If you have a machine that delivers 4000 psi and pretty large spray tip, then you’ll have a lot more material being released, so the distance again, will be a bit further away from the surface.

The trick to spraying is moving your hand across the surface in one even stroke, keeping the gun the same distance away from the surface.  The speed at which you move through this stroke will also be dictated by the volume of epoxy being released.  Pond Shield epoxy can be sprayed down at 10 mils thickness in one stroke, so try and run a stroke and then stop for a moment to measure the thickness of the epoxy with the gauge.  If the coating is at 10 mils, then your distance away from the surface and your stroke speed are perfect.  If not, then adjust accordingly.  If the coating was thinner than 10 mils, you may have to move closer as well as slow your stroke speed down.

A caution should be mentioned here.  If you lay the coating down thicker than 10 mils, you may experience sagging.  The same can be said, if the epoxy is thinned too much. The main problem here is that you may not initially experience this sagging right away.  This may happen after you have moved on to another location to spray.  Sagging is an aesthetic issue and if it bothers you, you will have to clean that up later and possibly touch up those areas.

Immediately after you have sprayed all areas satisfactorily, you can begin the cleaning process.  This means that your assistance will switch from epoxy to a solvent like denatured alcohol, acetone or methyl ethyl keytone (MEK).  The acetone or MEK should only be used for cleaning afterwards and not in the pre-cleaning stage.  Spray the solvent through the lines thoroughly to ensure no epoxy residue remains.  Uses brushes and such to clean all of the machines moving parts, pick up tube and spray gun.  Afterwards, drain the hose of excess fluid before returning it.

The next day you will be ready to inspect and touch up the coating.  Keep in mind that even if the job was perfect today, it is not likely to be perfect tomorrow.  Concrete has a way of letting coatings settle in and there may be places to touch up before you fill the pond with water.  Always inspect your surface and tough up as needed.

Wooden Pond Structure Construction Materials

By | Wood Ponds

I think when a person has decided to make a wooden pond structure in this instance, the next logical step is to research they style they are going to build so that they may further educate themselves in any of the idiosyncrasies that may revolve around their project.

I talk to a lot of people about wooden pond structure construction and because of the Internet they seem pretty informed.  They know what shape the pond structure might be, they know where the structure will go and they even have a good list of support equipment necessary to run the wooden pond structure.

What they are usually missing is a good list of construction materials needed to actually build the unit.  Sure they might know they need wood, glass and Pond Shield epoxy but after that anything else is typically of generic nature.  So let’s talk about those briefly.

Wood – What kind of wood?  Well there are two types of wood.  There is hard wood and soft wood.  A typical hard wood might be oak for instance and pine is a soft wood.  What difference does that make, you ask?

Well the actual panels of the wooden pond structure can be made of soft wood like pine or fir plywood where the bracing might be made of a solid hard wood like oak or cherry.  Of course a typical soft wood pine 2×4 is plenty strong if used correctly.  Take a look at the Wooden Pond Structure article.

While we always recommend that sheets of hardy board concrete be used to line the inside of a wooden pond structure, they are not total necessary.  They are more a very big safety measure.  If you’re not going to use the concrete board, then the plywood you use should be of a wood that has a very tight grain.

Usually hard woods are tighter grained, but there are variances in all types of wood.  The tighter the grain, the less swelling or misshapen (as the wood accidentally takes on water) problems you’ll likely experience.  If the wood soaks up water, it can swell and becomes misshapen, which in turn can cause a delaminating of the coating that is applied.

Finally, make sure to use plywood that is an outdoor, marine grade.  These grades of plywood are assembled with water resistant glue which will cause you less headaches later as well.

Concrete Board – This is usually called Hardy Board.  There are two different types, one for shower pans and one for exterior siding.  The Hardy board siding is the only one you should use for a wooden pond structure.  The shower pan style is too rough and will only cause you to use more Pond Shield epoxy than you should have to.

If you do use concrete board in your wooden pond structure, then you’ll benefit mainly from removing the wood from and water barrier duty.  The further the wood is from the water, the less trouble you’ll have with it.  Now Pond Shield does stick to wood, but it sticks to concrete even better.  This is why we recommend using Hardy board.

Adhesive – Adhesive, for what?  Well if you plan to use Hardy board, you’ll need to glue it in place.  I have always used Sika-Flex A1.  It is a very strong construction adhesive that remains very flexible.  This means that even if the wood portion of the structure moves, it will not effect the interior concrete board construction, which could have led to leaks.

Fiberglass – No matter what you build your wooden pond structure out of, you’ll need to run fiberglass matt along the seams.  I recommend that you use 1.5 ounce chopped strand matt.  The thickness of the fiberglass and the chopped strands tend to dissipate stress quite nicely.

Fasteners – Ok, get a big old bag of nails for this.  No!  I’m just kidding.  Avoid using nails whenever possible.  They just do not hold on like a screws will.  Your choices of screws these days are a plenty.  I always use something that is stainless steel first if I have the opportunity.  The less corrosion your fasteners go through, the stronger your finished wooden pond structure will be.

I also use sheet rock style screws because they tend to really grab a lot better than typical wood screws.  This is not to mention that they usually have a higher tensile strength too because of the way they are made.

Silicone – If you plan to have a viewing window in your wooden pond structure, then you’ll need to adhere it to the walls in some way.  Silicone seems to be the best choice for that.  Look for an aquarium safe silicone to use for this.  You can usually find these online or at your local aquarium store.

Bulkhead Fittings – For wooden pond structures, these are the best way to get your plumbing through walls and floors.  They are usually made of a schedule 40 or schedule 80 PVC.  They are made up of three parts, a front have, a back half and a rubber gasket.  The gasket will always be on the inside of the wooden pond structure.

Various Brackets – Depending on how you construct your wooden pond structure, you may or may not use metal brackets.  If you do, be sure to use those that are galvanized at least.  This added layer of corrosion protection that coats the steel will make them last a lot longer.

Coating – No matter which method of construction you use, you will have to coat the interior surface in order to waterproof it.  Of course we manufacture the perfect coating for that purpose.

That is about all there is to the materials needed for a wooden pond structure.  If anyone out there has any other material ideas, let me know.

Water Proofing a Salt Water Aquarium or Tank

By | Aquariums

I am asked all of the time if Pond Shield will hold up in a salt water environment.  The answer is yes it will.  In regards to water proofing a salt water aquarium or tank, I am not going to talk about the construction of the tank here.

If you would like to know more about the actual constructions, then following this link: How to Build a Wooden Pond or Tank to the article I wrote about that.  If you have not seen this article and are considering building your own tank, I highly recommend that you read it before you start.  You will probably find some things in it that you may have over looked.

With that said, there are a few things you need to remember when coating any aquarium or tank, regardless of it being for salt water use or not.

If you are trying to coat glass, you are going to have to etch or rough up the glass first.  A surface like glass has no surface tension and without roughing that surface up, the coating will soon fall off.

When coating wood, it is best to thin a small amount of Pond Shield and coat the wood surface before coating it with a normally mixed batch.  This thinned down version of Pond Shield will act as a primer and drive little epoxy fingers deep into the wood grain where the bond will be that much better.

If you are going to have a glass viewing window in your salt water aquarium or tank, you will still need to coat the wood that the glass will rest against.  It is best to rough the coating up some after it has cured where the glass will rest so that when you use a fish safe silicone to seal it, the silicone will adhere better to the coating.  If you can etch the part of the glass where the silicone will come into contact, that bond will be much better as well.

Other than those things to remember, the coating process for a salt water aquarium or tank is pretty much the same as any other surface.

How to Rough up Concrete

By | How To

So if you want the coating to stick to the concrete it has to be at least a little rough.  If you have not acid etched the concrete yet, then you are in luck.  The chances are that when you do acid etch, the calcium sulphate will be removed from the surface and leave you with a more porous surface, which in essence equates to being more rough.

However, there are times that even after a good etching, the surface is still too smooth.  If this is the case, you will probably be stuck with either sandblasting or grinding the concrete to get it into shape.

If you are going to sandblast, be sure to choose a quality professional to do the job.  Sandblasting can make a mess and the last thing you need to worry about is the guy doing the job and whether or not he does that without making a serious mess or damaging surround items.

If you prefer to grind, then an angle grinder equipped with a flexible sanding disk that is about 36 or slightly finer will do the job as well.  Make sure you wear proper protective clothing as flying debris can damage your eyes.

Once all has been blasted or ground down, you will have to acid etch again, as the newly acquired surface will have fresh calcium sulphate in it that will need to be removed.

Is Epoxy Toxic to Fish?

By | General Tips

Is epoxy toxic to fish? That is a very valid question, is it not? There are a couple of things you need to keep in mind when trying to decipher this, especially if you’re building a water feature that is going to house fish.

First remember that generally, epoxies that can be purchased at local hardware stores may indeed be toxic to fish. This is because these types of epoxies have a very specific purpose intended for them and that purpose does not revolve around housing aquatic life.

Epoxy coatings can leach off toxins both before they are cured and after they are cured. For purposes of housing fish, it’s this time afterwards that is most important. You will have applied the epoxy and let it cure before filling you pond back up and if the epoxy leaches toxins off after the cure, then your fish are in danger.

So how do you know if the epoxy is toxic or not? Well the easiest way is to read the epoxy technical data sheet and the MSDS (material safety data sheet) provided by the manufacturer. These two documents, along with a chat from a representative of the company can help clarify that.

The MSDS sheet will contain general information about the epoxy, including handling information. The technical data sheet will have scores of information in it regarding the coating you will find test data that covers anything from strength properties to, yes you guessed it, toxicology testing.

So do not be afraid to ask for these documents. You might be amazed at what you can learn.

Koi Treats – What You Should And Shouldn’t Feed Your Koi

By | General Tips

There is a variety of foods available for Koi on the market today.  Generally speaking if you read the packaging of the food you plan to purchase it is almost like reading the back of a can of soup.  You will get to know what makes up the stuff you’re about to feed your Koi.

But what about other types of food or treats?  Do Koi even care for a treat or are they willing to taste test just about anything you throw in the water to them.  Here’s a reality check.  Would a Koi know the difference between a piece of brown bread and a piece of white bread?  I doubt it and guess what?

The white bread contains bleached flour that can cause the fish harm.  So the point is that just because the food is acceptable to you, and you have no trouble eating it, does not mean your fish can.

You will probably want to avoid any type of treat with a hard outer casing like corn or beans too.  Your fish will not be able to digest the outer layer and this can also cause them problems.  You can feed them lettuce or leafy vegetables like duckweed (as long as they are clean of pesticides) and your Koi will enjoy them.

I have heard that citrus is somewhat of a treat for Koi too.  But it has been said that you should only treat them to this once per week, if you do at all.

How about live food?  Yeah I know the thought of holding a squirmy earthworm above the water for a frenzied Koi isn’t the best picture I could place in your head, but people do feed them to their fish.  Just clean any dirt off of them first.

Ok here’s an appetizing choice for your Koi.  Young tadpoles.  Yeah this is even worse to think about than earthworms for me.  But apparently Koi love them, so a treat of these seems to be in order too.  You can probably find all sorts of freeze dried yummies at the local pond shop too that the fish will like.

Just remember to pick a treat that is actually big enough for the size Koi you have.  Daphnia fleas for instance, are great for fry, but way too small for larger adult fish.  Silkworm pupae are another great treat for Koi, but should only be a very rare treat and the high fat content can cause problems with Koi and diabetes later.

The best way to think about all of this is, to feed your Koi properly.  A good balanced diet with the proper amounts of protein, and vitamins is the best way to feed your fish and treats should be just that – treats.  Pick the treats carefully and make sure you are giving them something that they like and will not harm them.

Going Green – Efficient, Sustainable Pond Techniques

By | General Tips

With all that is happening in the world today, the last thing you might think about while enjoying your pond is how efficient it might be.  There are statistics being thrown around today that talk about the ever looming global warming, greenhouse gasses, CO2 emissions and all sorts of stuff.

I bet you did not know, but even when it comes to your pond there are a few things you can do that will make it more efficient and thereby waste far fewer resources like energy and water.  Let me throw this little fact at you.  If your pond is 10 feet by 20 feet and leaks just one inch of water, you are loosing 119 gallons of water.

If that water is left to flow down any of the local sewer drains, it is not doing anyone any good.  Even if the waste water in your area goes through a treatment facility and is brought back to be used in some way or another, your leak is causing the treatment facility to waste energy on that water too.

Now of course you might be sitting there thinking I am some sort of conspiracy theory nut or something, but it’s not true.  I just think that if it is important to you to separate your recyclables from your trash each week, then you might find this information useful too.

By the way here is my shameless plug in this article.  Pond Shield epoxy is a water proofing coating that will seal up leaks in your pond.  Using it will help you not to contribute to a waste of water in the long run.

Ok going back to water issues.  How often do you back flush your filtration system?  Once per week?  Twice per month?  Ok, what do you do with it?  Let it go down a drain somewhere?  Bad pond owner!  Bad!  You should set up a way to irrigate existing plant life in your yard.  That would mean less watering with your normal irrigations system and then eventually, less waste.

What about the chemicals you use in your pond?  Are they eco friendly chemicals?  If not, they all have to be processed out of the water eventually you know.  Again, that means more energy exerted in the actual processing.

When you purchased your electric motor for your pump, did you make sure you bought one that would do the job efficiently?  You know over working or under working the electric motor will waste electricity too.  These resources come from somewhere and at the source if it means the exertion to create the energy is more than being used efficiently, then that too is considered a waste.

I hear all of these commercials every day where they say is X number of people replaced their dish washer with a brand new energy efficient one, it would be like removing X amount of cars from the road.  Yeah that sounds weird, but if you always think about the source that produces the energy and how it has to work more in order to do a less efficient job, then you can see the waste.

Anyway, just a little food for thought.  If you were planning to replace something in your pond because it is worn out, now you can applied these concepts to that new purchase.

How To Purchase Quality Koi

By | General Tips

You know, purchasing Koi or any other pet is a pretty fun experience, but you have to remember that it or they are living beings and will need proper care.  Because of this you should make sure that your pond will be able to accommodate the Koi your purchase without breeching the limitations of your pond and its mechanical systems.

One of the things you may also want to consider is watching a particular Koi before actually purchasing it.  Of course this comes with the risk of someone else actually purchasing it before you get to, but if you keep notes on several Koi at your local dealer, you may find yourself with a better quality and better looking Koi than if you had just pulled one out of a batch of fry.

You will also have to decide where you will purchase.  They are Koi farms where they Koi are either bred or imported several times per year and there are retail locations that purchase from the farms on a more regular basis.  Where you might have more a selection at a farm, you will have multiple selections per year from a retailer.

They say that the best quality Koi are imported from Japan in November and December.  Typically, water temperatures are lower and can contain more oxygen for transport at this time and harvesting actually ends in October there.  Typically stateside Koi farms keep the same sort of breeding cycle if they breed their own.

When you choose a place to purchase from, make sure that the staff is knowledgeable about their stock.  They should be willing to answer and questions you have about the fish.  Take a look at the state of their ponds.  The ponds or holding tanks should be well filtered and clean.

Being a Koi enthusiast, you should remember though, that clean looking water is not necessarily clean.  Smell the water too.  Though this method is not a perfect science either, sometimes you can determine if there might be a problem.  Watch the fish for any signs of stress too.

When you decide on a fish that you like, watch it for a while.  Pay attention to how it swims and moves.  Make sure it is not bumping into things and that its movements are not sporadic.  Koi swim in a very fluid motion and look very graceful as they move.

Look at the way the fish breathes.  A Koi breathes slow and regular and you should see this in both gills.  Gills that are flared out are a sign of sickness.  Check the fish for any appearance of white blooms on the skin of the Koi, or raised scales, holes, cloudy eyes.  These are also signs of problems with the fish.

You should ask a staff member to separate the fish you like from the rest.  Usually they will put the Koi into a tub for this purpose and allow you to view the fish more closely.  Watch the way the person handles the Koi.  This will also tell you how capable they might be.

When catching a Koi for close inspection, a flat pan net is usually used and the fish is encouraged to swim into the tub by itself.  This method is less stressful to the fish and causes virtually now physical damage.

In the tub, you can look more closely at the fish for the things mentioned above.  Here you can also get a closer look at the fins for parasites and such too.  You do not want to bring an infested Koi back to your healthy pond and risk the infection of all of your stock.

Once you have decided upon a Koi, you’ll want to make sure you transport it properly.  It is recommended that you use a large bag for the fish and that the dealer oxygenate the bag as well.  I would also ask for a box to contain the bag and maybe even call ahead to make sure one is available.

You do not want to let the fish in its bag roll around the inside of your car on the way home.  This can seriously stress the Koi.  I would further suggest that you bring a blanket to cover the box with too.  Being in a dark environment will calm the Koi and it will be less likely to thrash about and possibly injure itself.

There are two schools of thought here in regards to quarantining fish.  Some say that this causes undo stress in the fish in that you end up having to move it twice and that the repercussions of these actions might not actually be seen until a lot later, months and maybe even years.

Others say that it is best not to introduce new fish into your pond because there may be a risk of contaminating the entire stock you already have.  While this is a possibility, you should consider that typically fish that are imported in, they are quarantined at that time.  Though this does not guarantee that you would not experience problems, it just gives you something to consider.

Ultimately, it is best to use your head when choosing and purchasing a new Koi.  This fish will be with you for a long time, so you want to give it the best chances it can get for survival.

Sealing Your Pond – A Simple Checklist To Prepare You For The Task Ahead

By | General Tips

The big day is soon to arrive.  You’ll finally get that pond of your back into waterproof shape.  You will be able to bust this job out in a day.  Well hopefully you will.  Best intentions and all that huh?

Well to ensure that you have a better chance at accomplishing your task in the time frame you want to, I have assembled a list of things you will want to go through and make sure you have completed before that day arrives.  This way your mindset can be on the project and not on what you may have forgotten.

Items Before Coating Day

Your new coating material – This is obvious.  You cannot start your project without the main material.  Also, you should think ahead.  Scheduling to waterproof your pond on a Saturday and ordering materials on a Friday might not produce the results you were thinking.  There could be issues with product availability as well as increased freight costs.

All instructions – You should read through all of the instructions prior to actually applying the coating.  This way if you have questions, you can ask the manufacturer for assistance.  Support may not be available on weekends.

Friends – Hit your friends up at least a week ahead of time.  You know as well as anyone that nice weather means people don’t hang out at home.  They go places and enjoy the outdoors.  If you need help, ask friends but give them plenty of time to schedule you in.

Preparation – Are all of your preparation steps completed?  Repairs, acid etching or anything like that will definitely slow you down on the day you plan to apply the coating.  Get this stuff done ahead of time.

Weather Forecast – Is it not always like this?  You get up to start that outdoor project only to find it raining cats and dogs.  Check your local weather forecast and make sure you have suitable weather.


On Coating Day, Prior to Coating

Consumable Products – Have you purchased all of the consumable products that you need for the job?  Paint brushes, squeegees, rollers, mixing buckets, cleaning solvents, cleaning materials, paint trays, are all part of the consumable products that you’ll need and not want to have to chase after once you have started your application.

Tools and Equipment – Drill and mixing paddle for the coating, gloves, eye protection, old clothes, extension cords, thickness gauges, any spray equipment you might be using along with an air compressor and tarps, are all of the tools you would need to complete the job.

You can download a checklist I created, by clicking here.  It is in PDF format so you’ll need Adobe Acrobat to read it.  Just visit adobe.com to get Acrobat.

Carbon Dioxide – Lurking Danger in Your Pond?

By | Water Quality

Carbon DioxideIf you have not taken the steps necessary to add oxygen to the water in your pond, the carbon dioxide levels may be higher than you think.  If they are, then the chances are that the concentrated levels of carbon dioxide in your fish’s blood streams may also be high.

You see carbon dioxide is more soluble in water than oxygen.  In fact oxygen levels in water become saturated at 9 ppm at 68F where carbon dioxide becomes saturated in water at .5 ppm.  In comparison to blood, the saturation levels are pretty close to being the same.

Fish will start to have problems breathing when saturation levels of carbon dioxide reach 5 ppm.  I bet you did not know it, but for every pound of oxygen a fishes breathes in, it exhales about 1.38 pounds of carbon dioxide.  That ratio alone puts the water oxygen levels at a deficit.

So what can you do about it?  Well remember we talked about proper pond aeration?  That is correct.  Pumping air into your pond will increase the oxygen to carbon dioxide ratio in your pond water and make things a heck of a lot easier for your fish.

There is also a by product of proper aeration.  As the air you pump into the water floats to the surface in the form of bubbles and pop, there is a gas exchange going on.  This is where carbon dioxide is released in the process which is good fro the pond.

So basically, it really is as simple as that.  I bet you were thinking this was going to be all complicated or something huh?  Well there is one more small detail that you might be interested in.

For those of you that have an indoor pond or store your fish in an indoor pond, you need to think about where all that diffused carbon dioxide goes after it leaves your pond.  Think of all of your family members plus yourself exhaling carbon dioxide.

If you combine that along with what is expelled from the pond, you too could find yourself in danger.  You might consider some sort of air ventilation to expel the carbon dioxide outside where it won’t be harmful to you indoors.  More elaborate systems could include a degassing column.

Degassing columns will strip the carbon dioxide from the expelled gas and return fresh outdoor air back into the closed environment.

Is Your Concrete Too Rough Or Too Smooth? – Fix Your Concrete The Easy Way

By | Concrete Ponds

8Sometimes concrete ponds are constructed and virtually no thought is given to how the surface should be in regards to it being able to accept a waterproofing coating later.  Sometime the surface is either too smooth or too rough and needs to be corrected prior to applying the coating.

I have seen people use brick in the ponds also.  Now brick is a funny material.  It is either too porous or ultra smooth.  Porous brick is not usually an issue because the pore can be filled, but ultra smooth brick can cause future delaminating if it is not properly surfaced prior to coating.  The techniques to handle this type of brick would be the same as with concrete to be explained here.

I find that one of the easiest ways to make a smooth surface more rough is to sand blast it.  Of course sand blasting has its pros and cons.  For one thing, it most certainly will clean a surface pretty well and give a nice texture to accept a coating, but it also makes a serious mess.  You’ll end up with sand everywhere and it will be there until your surrounding yard assimilates that which couldn’t be cleaned up.

Also with sand blasting, you’ll have to hire someone to do it.  It’s not likely you own the equipment necessary and probably do not have the skills either.  That is ok though, because there is at least one other way to accomplish this.

My favorite way is to use a large 8” angle grinder.  Suit up in protective eyewear and a face mask and you can go to town with a tool like this and either smooth out the concrete or rough it up as needed.  They work wonders.  Let me explain.

Flexible Grinder DiscIf you use a flexible sanding disc on an 8” angle grinder it allows you to cut away imperfections in the concrete while at the same time protects the concrete from you accidentally gouging to some degree.  This means you can float the grinder over the surface and follow the natural contours more closely without cutting away too much concrete.

Use a 24 grit sanding disc for the process as it will leave a more desired surface afterwards.  Not to mention it will last longer since it is coarser.  Be sure to aim the spin of the grinder away from yourself.  There’s no sense in directing debris right at yourself.  It not only hinders your sight but the flying debris can injure you as well.

Take Gunite for instance.  Usually a Gunite installer will assume that you plan to apply a plaster coating to the new pool or pond and he or she will normally apply a broomed finish to the Gunite surface.  That is fine and dandy for a plaster surface, but no good for applying a coating.  If you apply the coating to a surface like that, you are likely to waste a bunch of material just trying to fill in-between the broomed gaps.

Finally, as I said before, this scenario works fine for smooth brick too.  If you can just give the brick a new surfacing, it will give the coating much more to grab hold of during the application process, which will give you a longer life with the coating.

Keep in mind that this process will also be helpful when smoothing out mortar joints too.  Sometimes masons can get a little slopping with their joints and there’s no reason to just coat over them as is.  Clean them up first.

Pond Volume and Square Footage – Simple Calculations You Need To Know – Part 3 Ellipses

By | Calculations

Oval PondAn ellipse?  What the heck is an ellipse?  Simple.  Ellipses are circles.  Ok, did that confuse you?  Think of ellipses as special instance of a circle, meaning if you have an oval shape, it’s still considered a circle, but a special case of a circle.

If you have an oval shaped pond, you need to perform calculations for ellipses in order to figure out square footage and volume.  So, when we spoke about circles and some of your calculations were based off of the circle’s radius, it will be the same with an ellipse, but we’ll use the radius measurement just a little differently.

Major axis – The measurement that consists of the longest radius length from the center of the ellipse to the outer edge.

Minor axis –  The measurement that consists of the shortest radius length from the center of the ellipse to the outer edge.

Take a look at these pictures:


With an oval shaped ellipse, you will have two radius measurements.  One is longer and will be referred to as the major axis, while the other is shorter and will be referred to as the minor axis.  Remember when you calculated the area of a circle, you multiplied the radius by the radius and then by Pi?  This works the same.

For an ellipse, you multiply the major axis by the minor axis and then by Pi.  So if the pond was a 20 feet long and 10 feet wide oval shape, you would calculate,
20 (major axis) x 10 (minor axis) x 3.14 (Pi) = 628

Do not forget that you will have to measure the circumference (perimeter of the pond) in order to have the total square footage of the walls of the pond.  This is where it gets a little scary.  Because an oval is essentially a squashed circle, there are a lot of variables that would have to be taken into account in order to calculate the circumference.

First let me say that I will show you the varying calculations and you are free to follow along if math is your thing.  However, you may find that simply walking a tape measure around the perimeter of you pond is much easier.  Ok here we go for the mathematic enthusiast.

The first calculation you can do in order to find the circumference is an approximation only.  This means that you have to be sure that your major axis is no more than three times longer than the minor axis and your resulting calculation will be within 5% of being true.  That is the approximation part.  Your calculation could be as much as 5% incorrect.  But hey, let’s look at it anyways.

You are first going to multiply the major axis by itself and the minor axis by itself, and then add those two products together.  Then divide that answer by 2.  Take that total and divide it by the product of Pi multiplied by 2.
20 (major axis) x 2 = 400
10 (minor axis) x 2 = 200
So now you have 600 /2 = 300
Now, 3.14 (Pi) x2 = 6.28
The divide 300 by 6.28
30 / 6.28 = 47.77 feet

Now again, I stress that this formula is an approximation and can be off, up to 5%.  So let’s just assume you wanted a formula that calculated the circumference of the oval shape almost exactly.  Well all I am going to do is just show you the formula because it is nothing short of horrific!

Circumference = Pi(3.14) x (major axis + minor axis) / 4 x [ 3 x (1+L) + 1 / (1-L) ] And that’s assuming L = h/4 = (major axis – minor axis) x 2 / [2 x (major axis + minor axis)] x 2
As well as assuming h = (major axis – minor axis) x 2 / (major axis + minor axis) x 2

Now do you see why I say that it is probably just easier to walk a tape measure around your pond?  There is just no way I even care to calculate the circumference when it would take less time to physically measure it.  I certainly do not expect you to either.  So save yourself the time and headache and just tape measure the circumference.

Now that you have the circumference measurement, you need to multiply that by the height of the pond, like this (assuming the height or depth is 3 feet):
47.77 (circumference) x 3 (height) = 143.31 square feet

So the floor area square footage plus the wall square footage would be:
628 (floor area) + 143.31 (walls) = 771.31 total square feet

Again, to calculate how much Pond Shield epoxy you would need to coat this pond, you divide the total square footage by 60 square feet.  Remember 60 square feet is the amount of coverage a quart and a half kits gives you at a minimal thickness of 10 mils.
771.31 / 60 = 12.8 (rounded up to 13 total quart and a half kits)

To calculate volume of a oval (ellipse) shaped pond, you multiply Pi (3.14) by the major axis and multiply that by the minor axis and then multiply that by the height or depth and divide the total by 4.like this,
3.14 x 20 x 10 x 3 / 4 = 471 cubic feet

Then on to my obsession with water weight.  How much would that weigh?  3,956.4 pounds.  That is quite a bit of water for a small elliptical shaped pond.  Oh, I almost forgot.  Not that we have talked about elliptical shaped ponds, remember Part 2’s question at the end?  Have you figured it out yet?

I will see you when we discuss triangular shaped ponds in part 4.

Pond Volume and Square Footage – Simple Calculations You Need To Know – Part 2 Rectangles

By | Calculations

Rectangle PondOK, here are moving on to rectangles.  FYI – all of these particular calculations will work for those of you with square ponds too.  As I said in part 1 of this series, you’re going to eventually need to know the total square footage of your pond as well as the volume.

The square footage will assist you in calculating how much of any construction material you’ll need to actually build the pond and the volume will allow you to calculate the needs of water that your pond holds.

Squares are pretty simple to calculate too.  Unlike circles, there are only three measurements you’ll need to take in order to get the information you need out of your calculations.  There is length, width and height.

  • Length – This measurement is the longest extent of the pond, measured from end to end.
  • Width – The measurement is the longest extent from side to side on the pond.
  • Height – The measurement that is the longest extent from top to bottom of the pond.  You’d also refer to it as depth of the pond.


When we calculated the square footage of the walls of a circular pond, there was only one wall.  So keep this in mind when calculating the square footage of a rectangular pond.  It has four walls and all need to be accounted for.  Let’s assume that the length of the pond is 24 feet, the width is 14 feet and the depth is 4.5 feet.

To calculate the total square footage of the floor you would multiply the length by the width like this,
24 (length) x 14 (width) = 336

So the floor has 336 square feet.

For the walls, you would multiply the length by the height for each wall and then add them all together.  So,
24 (length) x 4.5 (height) x 2 (walls) = 216
14 (width) x 4.5 (height) x 2 (walls) = 126

So for this rectangular pond, add the floor square footage to both wall square footage totals and you will end up with a total square footage for the entire pond.
336 (floor) + 216 (walls) + 126 (walls) = 678

Again, to calculate how much Pond Shield epoxy you would need to coat this pond, you divide the total square footage by 60 square feet.  Remember 60 square feet is the amount of coverage a quart and a half kits gives you at a minimal thickness of 10 mils.
678 / 60 = 11.3 (rounded up to 12 total quart and a half kits)

Now because we already know the length, width, and height, it will be very easy to calculate volume.  As a reminder, it is important to know the total volume of water your pond contains for purposes of water chemistry or how many fish you can safely house.  You know, that sort of thing.

To calculate volume of a rectangular shaped pond, you multiply the length by the width by the height of the pond like this,
24 (length) x 14 (width) x 4.5 (height) = 1512 cubic feet

Do you know how much all that water weighs?  12,700.8 pounds!  Yes, I make a big deal out of the total weight of the water.  I will tell you why.  If you are planning some sort of holding tank, something indoors, something on a pedestal of sort, weight becomes a serious issue and you need to know what that will be in the end.

Next time we will talk about ellipse shaped ponds and how to calculate square footage and volume for those.  I will give you a hint.  They are similar in nature to a circular pond, but do you know what the difference is?  I will let you know in part 3.

Pond Volume and Square Footage – Simple Calculations You Need To Know – Part 1 Circles

By | Calculations

Round PondNow that you’ve gotten your pond built, it might be a wise idea to know both the total pond square footage and the pond volume.  Sure you can find an automatic calculator online somewhere, but it pays to have the calculations referenced and at least understand how they work.

Let’s talk about square footage first, since that’s probably going to be the first piece of information you might need to know.  It does not matter whether you are lining your pond with a rubber liner, Polyurea, or you plan a structured pond that can be waterproofed with Pond Shield epoxy.  In any of those scenarios, you will still need to calculate the total square feet of the pond.

There are some very basic shape categories that almost any pond shape will fall into.  Circles, ellipses, rectangles, polygons, general triangles and right triangles.  If you have trouble deciding, picture your pond as though you were floating above and looking down at it.

One point I would like to bring up before we move forward is the actual volume of a single cubic foot.  One single cubic foot will hold 7.48 gallons of water.  As a side note, one gallon of water weighs 8.4 pounds.  So, on cubic foot of water volume would weigh almost 63 pounds.  That does not sound like much now, but just wait until you see how many cubic feet of volume your pond ends up being!

So today, I would like to talk about calculating square footage and then we’ll move onto calculating volume for circular ponds.  These are pretty basic shapes and the formulas are pretty simple.  Typical terminology for circles would be radius, diameter and circumference and for volume you’ll use height.  Of course then there is also Pi.

  • Radius – The radius of a circle is measured as exactly one half of the diameter.
  • Diameter – The diameter of a circle is measured as the length from one side of a circle to the other side, using the center as an intersection point.
  • Circumference – The circumference of a pond is the measurement of the outside shape or outline of the circle.
  • Height – This is simple, it is the measurement of how high the walls of the circle are.
  • Pi – This is my favorite.  It even has a symbol   It represents the ratio of any circle’s circumference in relation to its diameter.  Confused yet?  Not to worry.  For the most part, it will be represented as a number in our calculations.  That number being 3.14.

So with that said, let’s see what we can do with that information.  If you plan to calculate the total square footage of your circular pond, you have to know the radius, the circumference and the height.  So let’s say that your pond has a radius of 10 feet, meaning that from side to side it is 20 feet (diameter).  Knowing this will enable you to figure out the circumference.  Let’s say that:

Height = 3 feet

Radius = 10 feet

Radius x 2 = Diameter (20 feet) Just showing you this so that you see how radius and diameter relate to one another
10 x 2 = 20

Circumference (62.8) = Pi (= 3.14) x Diameter (20)  So you multiply the radius times two in order to find the diameter and then multiply the diameter times Pi and you will have the circumference.
62.8 = 3.14 x 20

So to calculate the square footage of the walls of the circle, you multiple the circumference by the height.
62.8 x 3 = 188.4

The floor of the pond would be calculated by multiplying the radius by the radius and then multiplying that total by Pi.
10 x 10 x 3.14 = 314

Finally the total square footage of the circular pond would be the total area of the floor added to the total square footage of the walls.
188.4 + 314 = 502.4 square feet

Now to figure out how many kits of Pond Shield epoxy you are going to need to coat the project, divide the total number of square feet a kit will yield by the total square feet of the pond.

A quart and a half kit yields 60 square feet of material at a thickness of 10 mils.  10 mils is the recommended minimal thickness that the epoxy should be applied.  So,
502.4 / 60 = 8.37 kits (round that up to 9 total quart and a half kits)

Fortunately, the volume of this type of shape is simple.  You already have all of the components to calculate square footage and some of those will allow us to calculate volume.  In doing so, we’ll multiply the radius by the radius, and then multiply that by Pi, and finally multiply that by the height.  So,
10 x10x 3.14 x 3 = 942 cubic feet

The over-all weight of the water is simple too,
942 cubic feet x 8.4 pound per gallon = 7,912.80 pounds.  I told you it would be a lot!

Check back tomorrow and we’ll look at another shape and its calculations.

Pond Algae – Six Ways To Control Pond Algae Growth

By | Water Quality

Filamentous AlgaeOh yeah!  This is my favorite part of pond maintenance.  Not!  That darned pond algae, I just hate it.  It is always a mess to deal with.  Fortunately there are some ways to control it so that during your pond maintenance phase, the task of cleaning it up will be much easier.

By the way, did you know that there are thousands of species of algae?  Though you may never notice, over a period of time you may never have the same dominant species of algae in your pond more than twice.

Do you know that long, thin algae that is referred to as string algae?  That type, along with black algae is a filamentous type of algae.  You will find them attached to something in the bottom of the pond.  They usually float to towards the surface where the process of photosynthesis can occur.

Sometimes you might notice floating particles in the pond water.  While some of those particles can simply be dirt or pollen, some of them can also be planktonic algae.  This is the type of algae that actually changes the color of your water.  You know what I mean.  Has your pond water ever turned pea soup green before?  That is caused by planktonic algae.

Some algae will be attached the walls of the pond, small rocks and even your waterfall.  This periphyton type of algae will resemble a slimy, green layer on those surfaces.  Of course all of these algae have one thing in common.  They all thrive very easily in a pond environment.

Your task is to keep their growth in check so that they do not overwhelm the filtration system of your pond.  Here are six ways you can make the task of controlling algae in your pond much easier.

Physical Removal – You can easily remove filamentous algae (string algae) with a small algae rake or fork.  Just like twirling up spaghetti on a fork, your twirl up the algae.  Pull it out and throw it away.

UV Lighting – By sterilizing the returning water after it has been through the main filtration process, you can effectively disrupt the reproductive process of planktonic types of algae.  This will help keep the water crystal clear.

Lighting – If you have the ability to control the amount of sun light your pond gets, you can effectively retard the growth process of algae too.  Using trees, or some sort of shading mechanism will not only be a deterrent in algae growth, but your fish will enjoy it too.

Nutrient Rich Water – This is about the hardest way to control algae growth.  The problems is that your pond water is almost always nutrient rich and algae loves nutrient rich water.  They thrive on it.  Well in reality, they thrive on the phosphorus portion of those nutrients.  That is the part you can attempt to control.  If you use phosphorus removing agents in the water, you will deny the algae one of its main supplies of food.

Barley Straw – This is a good organic way to prevent algae in your pond too.  Floating a bag of barely straw will help increase the oxygen level in the pond and we all know algae is a plant and plants do not like oxygen.

Algaecides – In my opinion, these are the last resort in algae control.  I only feel this way because you are in essences adding a chemical agent to the pond that will kill the algae, and if you are not careful, you can kill other plant life in the pond as well.  Of course the downside of a chemical treatment is every time you change water, the algae can bloom again because the chemical has been dissipated.

Have You Ever Considered An Indoor Pond? 4 Things To Consider With An Indoor Pond

By | General Tips

When you think of a koi pond, you usually imagine something in someone’s backyard.  Maybe a waterfall with a small stream leading to a bigger pool where all of the fish are kept.  Lots of nice plants surrounding it, giving it a natural look that blends in with the outdoor décor.

Well what if you do not have room in a backyard for a pond?  Maybe the inside of your home can actually house something nice, but have you given any thought as to the needs of an indoor pond?  Here are 4 things to consider with an indoor pond.

The filtration system – Well if you’re going to have a pond, you’ll need to keep it clean right?  Keep in mind that just because the pond will fit indoors, you may have to squeeze your filtration in somewhere too.

Give the actual plumbing some thought too.  You will have pipes that will need to get to the filtration system as well as the rest of the equipment used to keep your pond clean.  You may have to get creative in how any of the plumbing is run.

Heating – This really depends upon where you might actually have the pond.  Some people put their indoor ponds in the basement where it can be quite a bit colder.  Because the pond is not out under direct sunlight, it will not be heated naturally.

If you have ever paid attention to an outdoor pond’s water temperature, you’d see that even though the ambient outside temperature fluctuates quite a bit, the water temperature will not change as much.

Water Changes – You will still need to perform water changes on your indoor pond just like one outdoors.  This means you will have to take into account any water that may be spilled during the process.

Like the rest of the pond’s plumbing, you should also consider special plumbing needs for this sort of maintenance too.  Back flushing a bead filter can be a messy process that you just take for granted when you’re outside.  Who cares if water and muck splash around a little?  But you sure do not want any of that on furniture or other indoor accoutrements.

Escaping Animals – You know, one thing I have learned about turtles is that you may give them the Taj Mahal as far as a living environment, but if they don’t like it, they’ll just simply leave.  Turtles can be funny like that.  They seek their own solitude.

Think of that in the house.  You might not want to spend your days looking for Scooter the turtle under all of the furniture.  Oh and what about those fun loving Koi?  Yes Siree!  Some of them like to breech.  When that happens, you may find one hopping around on the floor.
Those are just a few of the things one ought to keep in mind with and indoor pond.  That is certainly not the end all be all of lists, but some of the more important things to keep in mind.

Pond Aeration – Oxygenating Your Pond Equals Great Pond Health

By | Water Quality

Did you know that when oxygen levels in the pond drop, that the biggest Koi are effected first?  It is a fact.  Their massive bodies in comparison to the smaller fish in the pond consume much more oxygen.  The lack of therefore, causes them problems first.

Some of the key components that assist in the decrease of the Koi pond’s oxygen level are:

  1. Higher Temperatures – When water temperature rises, it simply cannot hold the gasses that are usually trapped in it.  This is not only true for oxygen but for all gasses like nitrogen and carbon dioxide.
  2. Contaminants – Any sort of contaminant including an over abundance of fish waste will also cause a decrease in oxygen levels.  This is why it is so important to monitor water chemistry on a regular basis.
  3. Poor Water Circulation – If you are not moving enough water in and out of the pond to be filtered, the lack of circulation will cause contaminants to build, which in turn decrease the oxygen level.
  4. Salt – Yes, salt is used in certain quantities to help aid in the fight against parasites and such, but the salt level will also assist in decreasing oxygen levels.

Aerating the water is as simple and providing a way for the atmosphere and the water to mix.  Water flowing from a waterfall into a pond or the use of air stones or other devices will make this mixture happen.

You might think that the mixing occurs when the bubbles are under the surface of the water, but this is not true.  The actual mixing process happens when the bubble burst on the surface of the water.  So having not enough bubbles or bubbles that are too large only make the transfer suffer.

This is why it is preferable to have the air to water exchange happen with an aeration system from a device like and air pump rather than just rely on the exchange made by a waterfall.

More oxygen in the water will also aid in the growth of good pond bacteria.  This is especially true at the beginning stages of creating a pond.  At that point you want to encourage a lot of bacteria (good) growth for your biological filter media.

Have you ever noticed that some pond keepers have their aeration system set just on top of the drains in the very bottom of the pond?  Because the water is being drawn from the bottom, this aeration system will circulate the pond’s total water column better.

You should never think that just because fish can breathe in water that they actually have enough oxygen to breathe.  This is a mistake.  Fish need oxygen.  Good bacteria need oxygen.  It is your job to make sure that they always have it.