how deep is your pond?
I know the experts say minimum depth for a pond with koi is 3 feet. Our current pond ia 100 gallons, deepest part is 18". We have one koi that is about 9" long, another new one that is about 4" a few goldfish and a small turtle. We are planning a larger above ground pond in the coming months. From an aesthetic standpoint, 2 to 2 1/2 feet deep would work best. I would be interested in others with koi in shallower ponds sharing their experience. By the way, new pond will be almost 1000 gallons. We have extremely mild winters here, and have had no problems with predators. Also, everything has done great in current pond. Thanks for your input!