I know everyone doesnt have a UGF, theres a guy I know of on a different board who has had his reef tank running for 37 years on a reverse flow UGF. That still des not negate the fact that while some is good, alot does not mean better. While normally I dont consider snails part of a bio-load, when you have them in those numbers, thats alot of poop pellets that no doubt have an effect on things.