My monitor recently died, and I moved my turtles into his tank (so no more plans for a pond). It's a custom glass deal, 5.5'X3'X30", I don't know gallons. Got it used cheap from a guy quitting cichilids.

Anyhow, my RES is loving it, but is there a bottom feeder that's more or less safe from turtles? There's debris from his feeding and the like, and I'd like to find some fish or inverts or something that'll scavenge that stuff up.