Thanks all for the DE tips, I now get DE quality filtering with the ease of sand.

I'm pretty much sold on adding a little DE into my sand filter. After a recent experience with Algae and then cloudy water for the first time (because I let my Chlorine drop too low after a few days of rain and 85 deg water) I had algae growing a fair amount. After brushing and treating the Algae my water got cloudy and did not clear up after a few days. So I added some DE into the skimmer and clarifier (once) to the pool and the water started clearing within hours. I'm not really sure how much the clarifier helped since I've never used it before. I did have to backwash and vac daily for several days, and I kept recharging the DE after each backwash and the water kept getting clearer and clearer.

That was a week ago and my water has never been clearer! It always looked crystal clear before using DE, but at night I'd notice a little fogginess in front of the light. Since using the DE that fogginess is virtually gone and the water is "severe clear."

My only technical input for people, based on my experience, is that I had to add too much DE to get a 1 lb rise ... I had added many, many cups before I saw a pres rise. So I abandoned that and now just add about 2 cups mixed with water slowly into the skimmer. No pressure rise but it really seems to help. With DE added my filter runs around 18 PSI, same as without DE.

Thanks.

18x36 IG vinyl 24k gal
200 lb starite sand 1 hp starite pump