Water is bypassing cartridge filter

[neags23]

I have a cartridge filter for an above ground pool that doesn't seem to be filtering. When I vacuum, any dirt, debris, or algae flows right back into the pool.

I've checked the cartridge, there are no tears or holes. I've tried a different cartridge.

The only thing that seems out of the ordinary is that at the bottom of the cartridge housing, there's a little floaty thing in the return pipe that the cartridge surrounds. The floaty has a flat side and a rounded side. I don't know which should be facing up. Doesn't seem to matter, though, as I've tried both.

When I leave the filter running over night, in the morning if I take the cap off the cartridge housing, it's only about 20% full of water.

The pressure gauge isn't abnormal.

I was able to fix this once by closing a valve to the pool for a split second to make the pressure spike. I don't know if that knocked something loose or what, but it seems to have only been a one time fix.

Any help would be greatly appreciated!

 

[Trick]

Are you opening the air release valve on the top of your cartridge housing? Let the air out to make room for the water.

 

[neags23]

Yep, I do that pretty frequently already.

 

[neags23]

Well I bought a new filter, using the same pump... Same issue. Vacuuming causes any sediment to go back into the pool. After a day, you could see that only about a quarter of the cartridge was filtering water. I bled out the air when starting the pump, too.

So I guess it's a pump problem? Could the pump be pushing too much air into the filter?

I guess I'll try buying a new pump...

 

[wjr75]

Not sure what type of filter you have but make sure you are seating the cartridge properly in the housing. My Sta-rite has two pipes on the bottom of the filter that the cartridges need to be set on properly. I doubt your pump has anything to do with it. Maybe try posting some pictures of your setup.

 

[Racer_X]

I'm by no means an expert, but from what you are saying it isn't a pump problem. If the water isn't getting filtered, then either the filter isn't seated properly (as stated by wjr75 above) or there is some other problem allowing the water to bypass the filter. It sounds like the little floaty thing is a check valve to prevent water from draining back out of your pool into the filter (?). The more I think about it, it has to be something with the filter not being installed correctly. Water will follow the path of least resistance...filter = resistance, filter bypass = no resistance.
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