We stocked rainbow trout 1-3lbs in 2-3acre pond with lots of natural food on June 30 fresh water is pumped 2-3 times a week untill it goes over the spill way. we put about 100 fish with more fish stocke last month now these new fish are turning dark maroon with some getting red gills o2 is at 120 and pump in water comes right from the river. the fish just sit around wont eat it seems and will swim on top of the water we have lost 2 and when one dies it goes back to its natural colors. first time this has happend in about 7 years natural plant growth lots of bugs and fresh water shrimp and a lot of the rainbows still swim and eat as normal help thx Paul