I wish that I had sump on this tank! It's not that I can't vacuum everything, it just seems never ending. I usually do a 50-60% change once a week and maybe a smaller one in between if I see too many logs of crap. Perhaps I just haven't really taken into consideration how much crap he produces. His diet is pellets, roaches, lettuce, squash, bananas, grapes and the occasional chunk of turkey hot dog. I feed once a day 3 x's aweek and twice a day for 2 as much as they will eat in 5 minutes or so. Almost to spite me he usually craps a lot right when I'm finishing a water change. What an ******* he can be!