Is this cyano?

[WSM]

Had what I thought was GHA for a couple weeks. It died and this is slowly taking over. Appears to be cayno but wanted to get some other thoughts.

 

[Reefer Matt]

Had what I thought was GHA for a couple weeks. It died and this is slowly taking over. Appears to be cayno but wanted to get some other thoughts.

It looks like cyano to me. I don’t see long snotty strings like dino has. A microscope would tell for sure. I’d vacuum it out with a gravel vac, then increase the flow in that area. Last resort, try Chemiclean.