We have a good sized pond for the ducks and geese, problem is within a few days (usually 1 to 2) the thing goes green, so we are constantly cleaning the thing, and scrubbing constantly, putting in fresh water. we have kiddy pools too and they are changed 3 and 4 times a day, sometimes more. does anyone know of any way that there is to not have this happen? some people said by putting water plants it would stop this, but how would that work? our animals eat everything. someone else said pennies to help, and also to ward off any bugs, that made it worse. than others said rocks and the bottom. its a good sized plastic pond. so anyone know of anything to suggest? we have atleast 30 or so ducks not including the ducklings hatching and 4 geese...well....11 all together and a few more to come. so any ideas i appreciate. heres a picture of the pond, and a day or so after it was cleaned.