Maroon growth

[Jeff Rodgers]

I'm new to reefing. My 4 daughters pitched together and bought me a reef aquarium, the tank is an established system, the previous owner and I broke it down and set it back up at my house on 12/2/18. Things look pretty good all things considered. Recently I noticed a maroon colored growth forming on the live rock that is producing small bubbles. I've attempted to research what it could be but there are too many opinions to narrow it down. My tank is 90 gal. with a 40 Gal. sump, I have a light bio-load, I tested my water everything is good, CA is low (375) but I've ordered supplements for that. Here is a pic. of what I've got going on. thanks for any assistance. Jeff.

 

[Dom]

Hard to tell from the pic.

It might be coraline algae or maybe dinos?

 

[Jeff Rodgers]

Thank you for your answer I will do some research and see what turns up. Much appreciated.

 

[davocean]

Looks like cyano.
If it blows off easy that is what it is, and pretty typical of newly cycled or disrupted systems like what you just did.

I'd step up WC's using good RO/DI water and siphon that out as you go

 

[Carterfish]

It is cyano. If I were you I would do a large water change. I know they make something that gets rid of cyano. Take the rock out and scrub the stuff off. It should come off super easily. This stuff is a pain and awfully unsightly. The reason you have it is because of excess nutrients.