I'm using the supernaturals white in my blackwater tank. It's got a really really really fine grain size, much smaller than I was expecting, but I must say it looks really awesome with the dark driftwood and black background. The way the reddish water reflects off of it also looks great. Pool filter sand scares me because I was once told that it's suitability for pool filters was because of it's sharp edges and particular shape (can't back that up though). Didn't have much of a problem with clouding myself...