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Seriously, I'd be curious to see where you mean? Not sure what a ring that floats around the filter opening is...
maybe I'm wrong, but that's never stopped me from putting in my $.02 before..... On the HS, the filter compartment isn't all under water, and I've found that the foam/slime/"stuff" can and does collect in the corners above the waterline. I guess it's one of those things that we're not told that needs to be maintained regardless of our tub setup...Anne, thanks for bringing this to our attention, it's about filter/compartment cleaning time for me again, anyhow.
All the parts of that item in both pictures have water going over them. It would seem to me that the only way for it to get that gross was the either the part too high or the water too low.