Cartridge Filter is only getting half used

[ozzz1]

For a few months I'm only getting a half dirty cartridge from the bottom up on an in ground pool. We had a small leak that was fixed. Otherwise, it's working great! But only using the bottom half of the filter. The only thing I've really noticed is the pressure reading starts at 8 with everything clean rather than 10 lbs.
Any ideas would be welcome.
Thanks in advance.

 

[PoolGate]

Do you bleed the filter? There should be a valve at the top. Let it run until just water comes out.

 

[ozzz1]

Yes, have tried that a couple of times. Doesn't change things. I will say that there appears to be a lot of air in the filter.

 

[ozzz1]

Also, the pump side is working perfectly with no bubbles/air

 

[proavia]

Yes, have tried that a couple of times. Doesn't change things. I will say that there appears to be a lot of air in the filter.

On a continual basis?
It's either a suction side air leak when the pump is running or possibly air is getting in somewhere allowing air to accumulate in the filter when the pump is off.

What is your pump runtime?
Does the air accumulate in the filter when the pump is on or off?

 

[ozzz1]

Def while it's on