Magna-Flo cartridge filter help

[Faulksy]

Hey Everyone

I currently having issues with my pool. When i clean the cartridge filter the pressure is good and the salt water chlorination is full of water but after about 30mins the pressure drops off and there is minimal water in the salt water chlorination. I think it has something to do with the cartridge filter as it was doing similar things when i got a new one about 8 months ago.

Could it possibly be something else or do you think i need a new cartridge filter since the filter isnt that old.

If it is the cartridge filter does anyone know where i can get a new one from. I cannot find anywhere that sell's replacement Magna-flo cartridge filters. Not sure on the model however the measurements for the filter are (Height) 540mm, (Width) 180mm, (Hole) 77mm.

Any help would be greatful

P.S im from Australia incase thats needed

 

[Bama Rambler]

What is the filter pressure right after you clean the cartridge?
What does the water look like?
What is the filter pressure after it drops off.

Something sounds wonky here. If the filter is clogging quickly you should be seeing the pressure rise, so I don't think it's a filter problem.

Does the pump basket stay full of water the entire time or does it get air in it?
Is the skimmer weir (door) working correctly?
Where is the water level in the pool?