Okay, I opened the pump lid and cleaned out the basket. There was debris in it, but it didn't seem that bad, that my pressure should be going down. I put the lid back on (and poured more water in, just in case, then started the pump. Now it is reading no pressure (or maybe a psi of 1). Water is coming out of the returns, and I can see the water go through the pump. But one thing just occurred to me - could the water level in the pool be too high? We've had a lot of rain the past week, and the water level is right about to the top of the skimmer opening. I'm at a total loss.