If you're all talking about Silica sand it is very cheap. Like $8 for a 40 or 50 lb. bag. The thing about this stuff is that it's really bad to breathe in the dust from it! So wear a dust mask while you wash it off the first time. Also, it has some really sharp pieces in it. ** I used the tube from my gravel cleaner to put sand into tank: Fill the tube with the washed sand. Then with hands coverings both ends, hold it over the part of the tank you want it in. Take hand off bottom of tube and put that end into tank and slowly let air into the top of tube. This way, the sand slides into tank with out a big mess. Hope this is helpful.