Brown Stuff on Rock

[wranodj99]

What is this brown stuff on rocks? It generates air bubbles. Bacteria slime? I carbon dose 40mL/gal vinegar in ATO in a 135 gal system with 50 pounds dry and 50 pounds live rock. Want to grow SPS. Added a dual chamber GFO/ carbon reactor last week.

Ca = 500
Mg = 1400
NO3 = 5
Kh =9.8

 

[ecam]

Looks like the dreaded dinoflagellates
Blackout (3-5 days )and peroxide ( 1ml per 10 gallon ) worked for me recently

 

[Brew12]

What is this brown stuff on rocks? It generates air bubbles. Bacteria slime? I carbon dose 40mL/gal vinegar in ATO in a 135 gal system with 50 pounds dry and 50 pounds live rock. Want to grow SPS. Added a dual chamber GFO/ carbon reactor last week.

Ca = 500
Mg = 1400
NO3 = 5
Kh =9.8

Just out of curiosity, do you have a significant amount of coral that you need to be dosing for? It seems like many people experience bacteria issues when they try dosing before their tank needs it.
Just an observation.