If anyone is interested give this product a try. It's UNIMIN quartz sand size 2040. It can usually be picked up or ordered from a masonry supplier. I like it for many reasons. It is cheap @ $10 for a 50lb sack, it looks very natural compared to pool filter or play sand which can be too much of one color. The 2040 granuals are just the right size for most uses, they are big enough to allow roots to get a good grip and to keep it from packing down causing bacterial problems, and they are small enough to keep food from settling in. It rinses easily, it is easy to vacuum and best of all, to me anyway, the granuals don't have sharp edges that can injure fish that like to dig in it, especially bottom feeders with barbels.