I've been using FiberClear in my DE filter for years. It's less toxic and filters even better than DE. But my filter is an ancient old beast made of stainless steel. It's rusting pretty bad since we switched to saltwater, and the belt is warped and apparently not replaceable. We have new filter frames in it but it never backwashes completely which means I make my dear husband take it apart and wash it out every couple months. Needless to say, he hates the thing. So...I'm seriously thinking about switching to a sand filter with glass media. Check out this video from Pool School's YouTube channel that explains why. Also, he doesn't talk about the maintenance issues (sand filter is WAY less maintenance) and the water issues (backwashing is much easier which means a huge water savings and dumping less water means less replacing of chemicals and salt). I'm sold. I'll let you know how it goes.