Q. I have a dragon fish (Gobioides broussonetti) that is approximately 7 inches in length. It is kept in a 30-gallon brackish aquarium. My problem is that I cannot find any information on it other than what it eats. I would like to know more about its habits so that I could try breeding it, if possible.
A. This is one of those unusual fish (or creatures) that is so ugly it's cute. It is generally seen in aquarium stores as a 5- to 9-inch, slender-bodied fish that sits out in the middle of the gravel, ignoring other fish that swim near by. The biggest problem with this species is that it does not stay the same as it matures. Oh yes, it does stay ugly and might even get uglier, but it grows to almost 2 feet in length and eats almost anything it can get into its not too small mouth.
It is a member of the family Gobidae, and the American Fisheries Society has given it the official common name of the violet goby. Dragon fish is a trade name to help it sell. The primary range of this fish seems to be the low-salinity, muddy marsh habitats of the Gulf of Mexico and the Caribbean. It can be found on offshore sand bottoms and will ascend rivers to pure freshwater. Its range is from Charleston, South Carolina, all along the Atlantic and Gulf coasts to Rio de Janeiro, Brazil.
To my knowledge, it has not been successfully bred in the home aquarium, but it should not be too difficult if a large enough tank is provided and both sexes are present. I cannot even tell you how to determine the sex of the fish, as the only times I have seen mature fish in any quantity have been in collecting seines in southern Mexico. If I had to guess, I would give them a large tank filled with hard, alkaline water with a small amount of salt in it. Aquascaping could consist of a shallow layer of sand, a couple of large rocks and some pieces of driftwood. An efficient power filter should be used on the tank. Feed the fish heavily on worms, shrimp, scraped beef heart and cut fish. From then on, I would follow proper aquarium maintenance techniques and let nature take its course. Perhaps, if you are truly interested in this fish, you will be able to spawn them.