I do over feed my Oscars, not sure on the color of food doing it.
I was thinking that maybe the nitrates were doing it.
I have to do water changes once a week to keep them down.
I have backed down on the feeding of the oscars. I'll see if that helps.
there is not driftwood in the tank, so its not that.
what i feed them is:
Beefheart, shrimp, sardiens (spelling?),
flakes, pellets, crickets, guppies.
(Beefheart and flakes are red.)
I have to get a tester for Nitrates, I have one for all other tests
but i just take sample of water in to a LFS to test Nitrates.
scottie