Hello all. We took our camper out this past weekend after having used it a couple weeks ago and our cassette flush water tank has turned rotten! The DW was setting up the interior while I was working on the exterior and when she opened the toilet the smell was horrendous! Like rotten cheese. We had used our toilet over the memorial day weekend and refilled out flush water tank at a dump station and refilled with non-potable water (never had a problem before). This time when we would add water to the bowl a occasional black chunk or bit would come out. After determining that the smell was not going away we closed it back up and are in need of remediation. Any ideas how to clean out the flush tank? Would using bleach damage anything in the flush mechanism (manual flush) or the cassette blade? Possibly related, it appears that some waste /TP got stuck to the cassette blade mechanism during the last trip. My plan is to drain, rinse, clean the cassette tank as well (yuk). Thoughts about cleaning out cassette/blade components? Thanks in advance!