Use of Crazy Glue Gel to hold coral frags

yes, it is. There are certain caveats to it though, like you want to just glue the bony skeleton on SPS...new growth will grow right over the glue once its totally cured, but fresh glue can cause burns or death on that tissue. Most other things can be super glued, although from experience it can be tricky glueing some soft corals AND getting them to stay attached. But it has been a method used for a LONG time...it def can and does work
 
Yes, it's (cyanoacrylate) quite safe when used properly and rather effective for many corals. Generally, less glue is more effective. Too much in the wrong places, as stated above, can burn the tissue and/or cause it to die.

It can definitely be completely useless for some corals -- leathers and Xenia are ones that I don't even try to glue. Basically, if it slimes when handled or cut, it's going to be very difficult to glue.
 
I actually use a combination of glue and epoxy. A drop on the bottom where the coral will attach and a drop on the portion that will contact the rock. Works quite well for me. Be sure you get gels, too.
 
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