I just got a 55 gallon tank from my buddy. It had 2 sick looking Oscars, a pleco and a gold fish. When I picked it up i took every thing out dumped his gravel because I'm going with sand. anybody have any suggestions that i should be doing to clean and sterilize this tank? Also I'm sure i should put the sand in the tank before water? I've never set up a sand tank and want to do everything just right. any input would be greatly appreciated!! thank you, crusch84