I use hayward cartridge filter with a hayward power flo matrix 1.5hp pump and have seen an increase in the psi to 20 when it normally runs at 15psi. I see a difference in the water flow output also. I had cleaned the cartridge, even if it wasn't very dirty, and had seen the PSI return to 15 for a short time prior to this returning to the 20 psi. I don't want to continue running this at 20PSI and find out later that I had been damaging the pump at the result. Should I be concerned and if so, what can I do to troubleshoot the problem?