I used filter sand from a pool supply store, it was like 7 bucks for 50 pounds but it's a bit bigger sand, there's a TON less "extra" stuff in it and barely any fine particles, all I did was put the sand in my tank, fill it half way up, syphon it out, fill it up, syphon it out, then filled it up by putting a plate on top of the sand and pouring the water onto that to keep the sand from getting "blasted" by the stream of water and my tank was never cloudy. so I definetly think it was worth the extra four bucks then the trouble I'd have to go through to clean the play sand. (o yeah and it was easy to fill and empty my tank with my python syphon, I don't think I could live without that thing.