I've noticed a change with my pump over the last 10 days or so. Normally, the water level in the pump basket is right up against the glass lid. It was so full, that without an occasional piece of debris floating by, it almost appeared as if there was no water in it at all. It had been that way for years. Now however, it appears that the basket is not quite filling and there is a lot of sloshing. As I said, this is very out of the ordinary. The water level is still well above the intake into the pump, so no air is getting into the pump that I can tell, and the pump doesn't sound any different than before. I checked the impeller, which was clean. I checked for any side suction leaks and couldn't find anything. No bubbles being discharged into the pool. The skimmer and floor drains seem to be functioning as normal, though its hard to compare suction levels from before. Everything seems normal except the water level in the pump basket.
What am I missing? Could my pump be heading south? Could there be a clog somewhere in the underground piping? How do I check / fix it?
Any advice is greatly appreciated. Thanks!
15 x 35 rectangle inground, vinyl liner, 3' to 7', Jandy 'Stealth' 1.5 hp pump, Hayward cart. filter with chlorinator (not used), 1 skimmer, 2 bottom drains, 2 outlets back into the pool, Heatsyphon heater, Poolcover automatic cover.