I've had this forever. Gonna stop mixing my own saltwater mix (I use tap with salt and prime) and going to start buying real ocean water. Should I replace rocks completely or will this nasty color eventually go away?
Hard to tell what you are talking about from so far away. If it blows off it is cyano. That said, rock becomes live over time and colors up due to different colored algaes and such growing on them. The use of tap water could have easily lead to a parameter issue and there being cyano in the tank though.
I see spots of what looks like coralline and other than that it's hard to tell.
Don't see any obvious cyano.
Not really seeing what you are talking about, the rock looks pretty normal to me.
Maybe not enough/right type of light to promote the coralline?
Are you using the moonlights at night, or for long periods of time?
I do not - I'd like to however. Is that bad? I have my light on a timer 1 hour in the morning and from 6pm to midnight. Also it's in a shady place. Here's a close up. The color looks very dark to me and sort of yellowish. Not like what I see in stores or in other peoples tanks.