[karimwassef]

As I understand it, the red slime is not the actual cyano. It's a biproduct they make when they reach a critical mass.

I can't explain cyano or red slime either except that they can be extremely localized. My suspicion is that there's a local die off that they're feeding on. Not enough to impact overall water parameters to be off, but enough that they can feed and grow in place until all the dead material is consumed. Unfortunately, if their biproduct is toxic, they can create a localized zone that's inhospitable to anything else. As they kill more, the bubble grows... Like a bacterial infection on necrotic tissue spreading to nearby living issue and killing it.

I can't explain it but my dinos and cyano seem to be linked too.