i clean the screens and put it all back together. mix 6 bs of d.e. with water and slowly pour it into the skimmer while the filter is running and my filter works fine. 9 psi on the gage and good water flow. after about a month the psi starts to rise, that’s normal. when i backwash the pressure goes back down to 9 psi. the problem is it climbs back up to 20 psi in a day or two and i have to backwash again. i’ve tried adding different amounts of d.e. after backwashing but nothing seems to work. from adding no d.e. up to 3 lbs after backwashing (in 1/2 lb. increments). after a week or so of backwashing every couple of days i lose all faith in the integrity of the d.e. coating on the screens and i clean the screens again and start over. the guys at the pool store say i shouldn’t have to do that but they can’t tell me how to avoid it.