When I had a 250# sand filter I would always get a few tablespoons of filter sand in the pool every week. I used a sand/silt bag on the polaris to get it up off the bottom, so I know that it was #20 filter sand. I replaced the sand in the filter and checked every lateral for damage but still a little sand was on the bottom of the pool. I had to be wearing good goggles to see it underwater but I could feel it and it drove me nuts. In my opinion there should be NO filter sand in the pool, only in the filter.

So after several years of being annoyed I stepped up and bought a new DE filter. I don't mind the extra maintenance and no more filter sand in the pool, just red clay the black lab introduces.

You can call me hypersensitive but I hated filter sand in the pool and now I'm much happier. A cartridge or DE filter will get rid of filter sand in your pool but you have to be pretty annoyed by sand to spend the money on a new filter...

Good luck