In the past I've had sand instead of gravel, but I found it a pain because it gets sucked up in the vacuum, then i'd have to dump the dirty water through mesh to get my sand back, rinse out the crap and dump it back in, the fish get wily when you start dumping sane in. Plus the fish poop sits on top of stuff and I got tired of looking at it. But I noticed a lot of people have sand with their polys and knives, I love the natural look of sand and apparantly the polys have an easier time getting food from sand, any tips on sand types and living with it?