Again, my reference to Soybean's post was only relative to the tank not being a natural environment. A zoo is not a natural environment, but we don't feed the lions bread (so why feed [bread] flour to our fish?).
Shall I reference the bloke that said he only feeds his fish every few days.
Infrequently feeding 'ample amounts' is more likely over feeding that can result in the very things you speak of.
I'm only suggesting feeding modest amounts of high quality fish food twice a day, every day (more for fry). If all of the food is consumed and there is less waste, there is no polluting bio-load.
I think the fear of over feeding coupled with misinformation has resulted in many false notions and once the newbie hears it echoed a few times (often by other newbies), of course it must be true.