I have not seen Home Depot carry the plain pool filter sand - at least not during the "off" season (i.e. when it's cold out). They had the "Pool filter sand plus", which is NOT what you want. It's got chemical additives that would harm your fish. You want just the plain pool filter sand. I found it at a pool and spa store. It was like $12 or so per 50 pound bag (I needed 2 for my 75 gal tank).
