Not sure what it is and I can't seem to find any info online. There's little black dots all over all my rocks and it's spreading to the skeleton of some of my corals. Added a small piece of rock in (to see if it will spread to it), and within 2 weeks or so the black dots spread to it as well. Not even sure if it's algae. For some reason, coralline refuses to grow on my rocks, but doesn't seem to have an issue anywhere else, including the glass, the pumps, etc. The rocks are Marcorocks from BRS. The black stuff doesn't appear to encrust or connect together to form a "covering".
Maybe #reefsquad have seen this before?
Maybe #reefsquad have seen this before?
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