Fragging.

If your coral is over growing; you can slice of areas with a clean craft knife. You can also use the cutting to propagate a new coral, by simply attaching it to a small piece of live rock.
Oh the joys of fragging! I haven’t yet been successful in getting coral to attach to rock. I have tried using elastic bands, fishing line and even cocktail stick driven through the centre of the coral.
I had some success with superglue gel by Locktight, but after a few weeks the coral wriggled free. The only issue with loose coral is the cleaner shrimp roles the coral constantly off the rock face damaging it. Sadly the abuse took its toll.

Links to fragging below:

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