With my previous hermit crabs, I've used Eco-Earth, but with my new guy, I'm thinking of using play sand. Where can I buy regular play sand but not so much in large bulk? I know Home Depot has those 50 lb bags but I don't want to buy that much. Is there other sizes that are available? Also, I've read about keeping the play sand moist but how do I do it? And how can I keep it moist? Thanks in advanced!