AEFW you're looking for light brown to tan colored oblong flatworms. The ones I have seen looked like tiny flaps of skin squirming in the water.
Get a flashlight with red cellophane taped to the lens and look at night in your tank for possible pests eating your SPS. Until then, I'd cut what you have that's still good and remount on plugs. Didn't you run into STN or RTN on your previous tank too? I wonder if there is a connection...
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Illuminata 57gallon rimless <-- this is a lie!
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