My LMB wouldnt eat that stuff.
Your talking about the algae that looks like little fuzzys on the rock?
How is your clean up crew? I stocked up on hermits (didnt have any at the time) and with in a few days the Hermits had cleaned all that crap off the rocks... I also added 3 emerald crabs and a sally light foot crab at the same time and together they all did a great clean up job.