New to the forum. i have a small pond in the yard..8x10 app. and have quite a few Koi. this spring will be the 3rd spring for the pond. Last spring we started with about 5 fish and early in the summer found we have about 160 babies in the pond. We were very surprised as it just "happened" At first someone told us they were probably mosquitos but in a short time we discovered they were babie koi.