Ouch

I don't no diddley bout tongue coral, but is it slowly wasting, or showing signs of dead tissue? Problem with fraggin big LPS(non branching) is getting the tissue to seperate without harming it.
Have you tried an Iodine dip? I would start there I think and examine it closely to see if there are any parasites that may be causing problems. Hopefully someone else will chime in
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I'm not going to wake you, I'll go easy on your heart
I'll just touch your face and drift away , like smoke rings in the dark