I've always added a cup of DE to my sand filter to get the sparkly water, once i add it my water pressure drops a small bit from the return and i usually have to backwash every 2-3 weeks. I plan on adding a solar heater to the pool with about a 12 rise where the panel will be, i'm worried that will DE being put into the filter that i won't have enough pressure to make it effective. If i only add 1/2 or 1/4 cup of DE, is that still better then no DE or am i wasting my time? Just want to make sure i have enough water flow to hit the panel and come back.