I have a 500lb sand filter with a 2spd pump. Added some DE to sand filter on high speed. Do you check for 1psi increase on high or low spd. Also, my pressure never seems to go up that much 2psi after about 3 weeks of running. There is a difference in water clarity after I backwash. Normal pressure is 22psi on high and 8psi on low spd.
22k gal IG vinyl, spa
Any thoughts,
Thanks
Dave