It looks like a red turf algae.
What are you useing for lights?
What are your nitrites, nitrates at? We can be more help with the actual numbers.
Have you checked for phosphates?
What kind of flow do you have in the tank?
What kind of lighting?
When was the last time you changed the lamps in the fixture?
How often do you do water changes?
What kind of water do you use when doing water changes?
Why are you adding supplements?
Are you testing to make sure that you need those supplements?
What are the exact readings on your Nitrate and Nitrites?
The red stuff looks like Red Slime algae to me. It is usually caused by elevated levels of nutrients in the tank and lack of adequate flow.
Old lamps also shift the spectrum of light they emit. This shift favors nuisance algae growth.
You can try syphoning it out the next water change and increasing the flow in the areas where the red slime is growing.
I apologize about the message I sent with the pics. I had a bit of trouble and ended up sending an earlier draft of the email. Anyway, here is the info: the lighting is 10,000k (installed 10-14-13) and actinic (installed 8-28-13), and I replace them every three months. The actinic is getting due for a change, but it shouldn't be degrading yet.
As to the water flow, in addition to the filtering system, I have a power head in the tank. Because the water flow is very high when they're both on, I turn the power head off at night.
I do water changes every two weeks with salt water I get from my local fish store. Between water changes I level the tank off with RO.
I tested yesterday and the Nitrates and Nitrites were both at 0 ppm, ammonia was between 0 and .25 and the high range pH was at 8.2. I haven't checked for phosphates since I don't have that test in my kit, which is an API Saltwater
Master Test Kit. Are there kits that test for things like phosphates?
About adding supplements, I had a problem a while ago and the guys at the fish shop told me to use those two and it corrected the problem I was having so I kept using them as directed. Should I not add those?
I also feed the corals Marine Snow, etc., a few times a month. Thank you!
