I use playsand and have never had a problem. Aquarium sand is just too damn expensive.
What I did to clean my playsand was to put as much as I could carry in a bucket, and rinse it with a hose till the water ran clear, and then it was fine in the tank.
I use pool filter sand and I dont even rinse it (i'm sure with other brands you might have to)
play sand is a lot finer and needs to be rinsed more, and its harder to maintain IMO
That would be a pretty good start. I think I ended up putting 2 1/2 bags in my 135.
All of the hardware stores that have pool maintenance supplys will have it. Around here is 5 bucks for a 50 pound bag.
I have playsand in my tank. No problems, zero mainenance with my Malaysian Trumpet Snails. I didn't even wash the sand since the residual clay works as plant fertilizer.