Maroon Algae
 

I have a maroon colored algae spreading on my live rock. It is similar in color to cyano, but it is probably 1/4" thick and more white colored underneath. It is velvety to the touch and very difficult to remove. It won't come off with a turkey baster and I can not siphon it out. I can get some of it out with a toothbrush, but I can't reach in the nooks and crevices and it grows back rather quickly.

The tank is a 65 gallon reef with a 1" sand bed and 75lbs. of live rock.
It has a finger leather, a frogspawn, some button polyps, and 6 fish. Nitrates are less than 5 and phosphates are .02.

Thanks in advance for the help!

What you may have here is Gracilaria algae, Cotton Candy Algae, or Cyano.From what you described, I am leaning towards Gracilaria, because when I had Cyano, It came off with ease, and Gracilaria has the tendencies of what your describing.

Can you get a Picture of it?

your algae is very easy to beat with this method
http://web4.reefcentral.com/forums/s...2082359&page=4

post before and after pics I am certain it will kill all of it.

Reef264,

Sorry, I don't have access to a camera. I looked up Gracilaria algae and Cotton Candy Algae, and it is not either one of those. I have had cyano outbreaks before, and it's not that either unless there is a form I am not familiar with. It has the same color as cyano, but it is at least a 1/4" thick and feels like a piece of velvet.

I bet this is close?
look at the red algae surrounding the corals

http://www.advancedaquarist.com/2010/4/aquarium

a spot treatment with peroxide will wipe it clean off the rocks, making look like it was never in the tank in just a few days.

Alright that's fine, I can work without photos.You say it feels like velvet, It may be a Fungus.

Try Algaebase.org they can identify just about any kind of algae.

I would like to know how the identification went and how the outcome is going. It is impotant to know that if you used the peroxide method as a spot treatment the area of algae growth would be totally gone at this time.