Yes, Ethly Cyanocrylate is reef safe; however, I am not sure about that specific brand. Most adhesives will list chemicals that are part of their formula and if it lists EC as the only ingredient then it should be ok. I would also use a "Gel" version if possible. It makes it much easier to use. Here is a quick article on superglue and using it in an aquarium. Hopefully I don't get in trouble for posting a link to another forum. If it is not allowed, please let me know and I will delete it.
We all have projects or times when we need to glue something in our aquarium and knowing which product to use is not only important…
thebeginnersreef.com