Need help with ID

[Ommeh]

Hi everyone.

I've been trying to figure out what this is and if it's good or bad. Over the last few months I've been getting a great lime green on my rocks and I was told that it was the start of corolline. However the green is now turning black/brown.

I rubbed the rocks to see if it was cyano but it's stuck on there. Rubbing with my nail didn't do anything either.

Any help would be great!!

 

[Ocelaris]

I have some, I assumed it was just a dark corraline algae. Mine hasn't really made much progress, it's still in a corner on one or two rocks after the year or so. I think as long as it's not taking over its probably fine.

 

[Ommeh]

It's only on a few rocks ATM. Hopefully it's good lol!