Brown blob taking over my live rock!

It starts out in spots just like coraline algae and spreads like crazy! It's dark brown/maroon and has white (dead?) hair algea growing on it. Ugly stuff! Any ideas?

 

It appears to be "Red slime". Is it slimy and can be sucked off or scraped off or is it hard and encrusting?

 

I scrubbed it pretty hard with a toothbrush and the brown wont come off (but the angel hair did); it's encrusting.

 

I had a small rock in my tank that had lighter brown encrusting algae. It seemed to have vanished once the purple coraline took off, encrusted over it. But based off those pictures it does look like cyanobacteria (cleaned some knarly cyano out of my refugium today). Hows your water chemistry?

 

Correct me if I'm wrong but cyno is not encrusting. I should come off easily with a simple syphon. I can't get this off even with elbow greese.

 

I had the same thing on my LR and I sat there for hours scrubbing it off my tonga branch. I wish I had pics, I am very curious as to what this is. It is brown and it acts like natures shrink wrap. It encrusts to the shape of the LR and won't come off, even with a hard scrub brush.

 

You are correct, that is why I wanted to know if was encrusting. In my tank there are so many different types of Coraline with many colors. From what I have read the color variations come from different lighting spectrum and I have observed this with the various light combinations I have used directly relating to different colors of the Coraline. No real problem unless you don't like that color. If/when you change your lights, try different types and see if it changes color.

 

My guess is lobophora aka wafer algae,it can take over and smother low lying corals.I have been fighting a winning battle with it,for about a year.I'm using sally lightfoot crabs,supposely naso tangs eat it as well.It's almost impossible to scrub off,in high flow areas it forms whorls,which can be manually peeled off. Good Luck is it like in the pic below

 

Isnt that just another shade of coraline?
If it isnt slimy to the touch Id let it be....
Danny

 

I would agree about the Coraline if a strange thing didn't happen today. I scrubbed all of the white hair off of the rock yesterday and today, it came right back! It's only on the brown algae(?), no where else in the tank, so they must be related.