I had an issue with BBA in my small freshwater shrimp tank. I had bought some plants online and I believe they were contaminated. I ended up having to redo the entire tank and soak everything in peroxide for days to kill it off. Other things I just threw away.
Anyways, I noticed something odd in my utility sink. It is one of those older cement ones. It started getting black slime growing in it and this was about 10 days after cleaning out the old tank. I think the finish had been worn down and the algae may have gotten into the pores of the sink.
Is this possible?