i was thinking about turning my 55g into a chilid tank and getting a bigger tank for my p's. im wanting to get rid of the gravel and put in sand and was just wandering if anyone has seen a sand tank before and does it look good. also i have a underground filter system and two hanging back flow filters. obviously i would have to take out the underground filter system, but are the two back flow filters going to be enough for the chilid tank and also is there any special maintance on taking care of the sand. thanks for your advice and opions.