What kind of algae is this?

[funkejj]

This has been growing for a couple of weeks and I just want to know if we should be concerned. It is only growing on one rock right now and does not appear to be fast growing. Thanks in advance.

[willandmelsreef]

looks like cyano to me

[funkejj]

It does not blow off when I tried. It is hard believe it or not.

[that0neguy1126]

It looks like some type of Lobophora. IS it rubbery/slippery when you touch it?

If it is. I would QT the rock if you can with a few no light cycles. You can also chip it off with a flat head screwdriver.

A few things will eat it such as emerald crabs.

[mauger1]

+1 to the emerald crabs.

[bertoni]

If it starts to spread to unacceptable areas of the tank (esthetically speaking), I'd start working on nutrient control. It's possible that emerald crabs might eat it, but crabs can become predatory.

[T-dub]

My guess is scroll algae. Fairly slow growing and really doesn't hurt anything. Just a macro algae.

[funkejj]

I have looked at pictures of both Scroll Algae and of Lobophora. Wife is wanting a emerald crab as it is so we will try that for a start. Thanks everyone for your input on this.