Guest ArticlesGeneral TipsPond Maintenance Koi Pond & Waterfall: Top 21 Most Asked Questions Answered Q What is the ideal depth for a koi pond? A In my 25+ years experience, 4 to 5 feet is ideal. You need a minimum of 3 feet for koi fish for several reasons. Safety for fish from wading cranes they can not wade…ButchJune 1, 2023