Yesterday, I noticed our waterfall trickling and my vacuum style Hayward Navigator was not moving at all. I went over to the equipment and saw that the pump was running full speed but was only half full. I checked the filter pressure gauge and saw 33 psi. Normally 20 psi.
I just cleaned the filter last month but did not add DE because I wanted to add a Black Algae treatment. I spotted 10 or 12 small button size dark spots on the gunite surface so I added the algae treatment to my pool and the water started to bubble up on the surface as if I had added soap. It has been a week since I added the algae treatment and all the bubbles have now disappeared. I checked and cleaned all filter baskets, no joy. I added silicone to pump lid o-ring and verified a good seal.
Could this be an impeller issue? If so how can I be sure? What else could cause this, any ideas appreciated?
My pump is a: Hayward SP3400VSP EcoStar Variable Speed Pool Pump (2 years old)
Filter is: Hayward DE6020 with a 2-position backwash valve (10 years old)
Let me know if you guy's need more information.