ID Please

Hi, I have this brownish/reddish color algae. Been there for month now. Luckily, it only on 1 piece of live rock.

What type of algae it's?
It's harmful?
What should I do?

I have taken, 2 pictures. 1 with flash, 1 w/o flash. Thanks

 

That is cyano bacteria. Siphon it off often and aggressively. Keep your feeding light and use GFO to help get your nutrients down. Larger/more often water changes should help also. Clean your tank, sump and filters to remove any detritus.

 

Check your phosphate levels. Perhaps needing more flow in the tank also. ??

 

It is not harmful that I have ever heard, just a eyesore like green hair algae or any other type of nuisance algae/cyano

 

Can I take out that piece of live rock and scrub the algae off?

 

^^ Thank for quick respond's.

 

My return is 550 gph, and using 2 korolia 1050 gph. That still not enough?

 

Yes!

 

I running GFO reactor for 3 week now. And do 20% water change every month.

 

Do your water change every 2 weeks at the same percentage. Feed less if at all possible. Thoroughly rinse frozen food before adding to the tank.