I have a klir 7" drop in roller system and when it works it is great. I do have one annoyance that bugs me. It is the seal material for the unit sucks. It is floppy and folds over easily when I am trying to replace the unit after servicing. I had the idea of putting a pad on the top of the 7" hole the would seal when the until is dropped in. My issue is I have no clue what to make such a pad out of. I want something that will not leech nasty chems into the tank. Any thoughts??

