Cyano bacteria
If it's fuzz, then it's not cyano. Cyano is slimy. It could be what people call "red turf" algae.
red turf doesn't always come in a long hair form. Are your water parameters off?
"Red turf" is like saying "hair algae". These are very broad terms covering a lot of different variations.
I doubt a crab will eat cyano. I would try a turbo snail before that (for the turf algae....not cyano).