Pool opened to a green swamp pool. Original pool was a salt generating pool. New pool is a sand filter with a 3 hp pump. Over 30,000 gals of water. Kidney shaped. The psi starts at 30 psi when started. Jumps to 40 psi within 2 hrs. Have done many backwash procedures and rinse. Also ran a waste procedure. Pool has been stripped clean of debris from pool. Any reason why the pressure is so high and climbs through filter cycle.