[Jonesrd1]

Actually what you are observing could be a very common response of several dozen different genera and species to (relative to each individual organism) their response to either low nutrients or a reduction of nutrients. Each organism or a consortium produces a polysaccharide(s) that form a thick mucous like material that helps them keep nutrients and extracelular enzymes from escaping. These are very common in the deep sea and are often bioluminescent. I suspect that the rapid reduction of vinegar and ethanol (nopox) caused this response in your system. There are a zillion other possibilities, but this would be my SWAG. Ron