Well, after replacing the 1 HP pump with a 1-1/2 HP thinking the run from the skimmer may have been a little too long and having no luck fixing the problem. The PB decided the problem must be a defective cartridge. We received the new cartridge yesterday, put it in and everything is working perfectly! YEAH! And the 1-1/2 HP pump really moves the water much better than the smaller pump.

Thanks for your help everyone! I relayed any and all suggestions to the PB since I was totally without a clue.