Flow of water into pool decreasing over a few days


Bronze Supporter
Feb 5, 2016
We opened our pool about a month ago and all seemed well. We had the salt water generator cleaned this year and the pool is about 4 years old. I noticed that the flow into the pool was not as strong as it typically was and that there was a small air pocket in the pump basket. I back washed and the pressure went back to normal. However I noticed that there was a bunch of air blowing back into the pool after the backwash cycle. This keeps happening every few days. The last time this happened I tried to bypass the filter by putting it in recirculate and the pressure went to normal but again their was air coming out of the returns for a bit. I'm guessing this is a problem with the sand filter but is it typical to get the air bubbles too or does that indicate a new problem. The air entering the pool lasts for about 20 to 15 seconds. We have never had an algae problem and the backwash water has been clean. Thanks.


Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
Laughlin, NV
Typically this is a sign of the filter getting dirty, and possibly an algae issue in the pool water.

Air getting into the system comes from the suction side. So check the pump basket lid gasket, be sure it is lubricated and seals well, any valves, the wier door on the skimmer, etc.