Pump only kinda running, don't know where to look for issue

[emmaleena]

My pump is running at only 3/4 full of water. When I backwash or put it on waste it fills all the way up, but when it's on filter it only runs like this. If I turn it off and back on, it'll fill almost all the way with only a few air bubbles before going back down. The return jets are finicky, and only one is working consistently. I'm not sure what kind of issue I should be looking for, let alone how to fix it.

 

[Jafarus]

I would start with the easiest and cheapest question first. Is the seal gasket at the top of the pump basket in good shape and sealing tightly?

 

[emmaleena]

Not really, I have a replacement set in the mail. If this is the issue, would this fix it? And if it doesn't fix it, what else could it be?

 

[emmaleena]

I would start with the easiest and cheapest question first. Is the seal gasket at the top of the pump basket in good shape and sealing tightly?

I have replacement pieces in the mail. If these don't fix it, what else could it be?