Ok so pool went green, it has been very hot. I slammed it 3 days ago. Still somewhat green, then added 1 pound of DE (today) very slow to skimmer after mixing it with water in a bucket. Pool pressure went from 15 to 16psi. Now after an hour of adding DE pressure has jumped to 30 psi. DE has only been in there an hour. Is the PSI too high should I go ahead and back wash the DE? TIA