I wouldn't reccomend putting the cuttlefish in a reef, depending on what you feed it, if it doesn't have to look for food, it won't rearrange your corals looking for inverts and fish. And if it inks for any reason and your corals ingest it, good luck reviving them. For really good information on keeping cuttlefish, look up the UTMB in Galveston. I have more info if you're interested. They can live for a good while under proper care especially if you aquire them as juvies. Their life is shortened greatly however, if you breed them. Then their life span is roughly 2 yrs.