I've got some outside work to do this AM, but let me pass this on to the Unicel service manager; he's offered to help with questions like this, and they make good quality replacement cartridges for most filters.

However, it would help if you can give us the exact cartridge and pump model you have -- or the pool model. Or if you can send pictures to poolforum@gmail.com. Or you can try taking pictures with your phone, and texting them to (423) 300-6560, which is the PoolForum Google Voice number. (Hm-mh. I can't get that to work. I'll have to try later.)