i have several colt frags available for trade!

[Delphinus]

I think there must be a dozen different species of "colt coral." I too had a colt coral once, it never self-fragged, but it certainly did get very large. At one point it basically grew right up to the water surface and would have walked out of the tank if it could have done so. I unfortunately lost this coral due an unfortunate float valve mishap (never put a float valve for topoff on an infinite water supply such as your cold water line.)

BTW, I was at Big Al's today at lunch time (I needed some underwater epoxy) and I noticed they had our "mystery coral" in there (or something that looked very much like it) labelled as "white colt coral."

The one thing the frag you gave me, has in common with my old colt (and sounds like your colt coral) is how amazingly fast it seems to be growing compared to other corals in the tank. Perhaps it is a variety of colt after all.