May 21, 2016 #1 coralosity351 Active Member View Badges Joined Apr 26, 2016 Messages 162 Reaction score 59 Rating - 0% 0 0 0 What is this and is it bad?it's just in that one spot and hasn't expanded to anywhere else
May 21, 2016 #2 Bunnee911 Valuable Member View Badges My Tank Thread Joined Jul 12, 2011 Messages 1,307 Reaction score 861 Location Texas Rating - 0% 0 0 0 Can you get the rock out? Spritz it W hydrogen peroxide. Then be done with it.
May 22, 2016 #3 Salty1962 Wrasse and SPS Lover View Badges Excellence Award Reef Squad Emeritus Joined Jan 28, 2015 Messages 8,484 Reaction score 7,744 Location Charlotte, NC Rating - 0% 0 0 0 Looks like some cyano. Suck it out and check your flow and parameters