More DE?

[PoolDoc]

Problems like yours can result from multiport gasket failure. It's possible to replace these, but it often doesn't go well, due to the difficulty of removing old adhesive, and getting the new gasket to stick.

You'd stated earlier

I opened the filter and the grids looked fine with no noticeable tears or rips.

If there were -- in fact -- no failures internal to the filter, then the multiport is the next most likely failure. I don't really trust homeowner (nothing personal; just my experience here) evaluations of their filter's internal conditions, but I can't 2nd guess their judgement.

However, replacing a multiport tends to be a "go / no go" situation: you either get it replaced or you don't. So if you replaced the multiport, you'd either fix your problems or you wouldn't. If you did, great. If you didn't, then I would say, "Well the problem almost certainly is internal to the filter. You need to check it again."

As it turned out, you later stated:

Some were flexible at the top and I found a hole in the bottom of another. I am hoping if I replace the damaged grids, the problem will be fixed

but I hadn't seen that yet, when I recommended the multiport . . . even though I suspected it might be the case.

So . . . now you've seen how my mind is working, on the OTHER side of all these posts!

[Shifty]

Thanks for the reply Pool Doc.

I am thinking I am going to hold off until next season to replace all the grids. Since cleaning the grids and adding the fresh DE, the amount of debris out the returns has lessened to the point where I will need to vacuum once or twice a week. My thinking is that since I would need to remove the grids for the winter anyway, why not just start fresh next season and not risk damaging new grids over the winter.

[PoolDoc]

Sounds like a plan!