II. There’s a Dragon in my Tank!

Keeping the Dragon Goby

There are a few creatures that are claimed to be “so ugly, they’re cute” or
“so ugly, only its mother could love it”. This dragon is not quite the same.
The Dragon Goby is a gentle monster — it’s nowhere close to as mean and evil
as it looks. Although it looks like a vicious predator, it’s really the

You cannot help but notice its weird appearance — unlike any other fish I
know. Its tiny eyes, huge mouth and long dragon-like dorsal fin set it apart
from all other fishes. A lot of folks would call this fish ugly but I find it
very lovely. It is the largest goby in the Caribbean and the only one with this
distinctive eel-like shape. Yes, it looks like an eel with tiny, beady eyes that
rest near the top of its big head and a large mouth, lined with sharp teeth.
This fish also has a beautiful bluish/pink metallic sheen to it, and a long,
undulating dorsal fin, closely resembling the serrated back on mythical dragons
(hence the “Dragon” name). I’ve always compared it to the monster in the move,
“Alien”, that pops out of that poor fella’s chest, before slithering away. Now
THAT one is ugly!

Dragon Goby

With its long, serrated dorsal fin, it is easy to see where the common name “Dragon Goby” comes from.

Meet the Dragon Goby (Also Known as The Dragon Eel or Violet Goby)

  • Scientific name: Gobioides broussonetti
  • Distribution: Western Atlantic: from Charleston, South Carolina southward to
    Florida, along the Gulf of Mexico coasts of Alabama, Mississippi, Louisiana,
    and eastern-central Texas; along the Caribbean coast of Colombia, eastward to
    Venezuela, Surinam, Guyana, French Guiana, and Brazil as far south as Rio
    Grande do Sul, Brazil.
  • Size: Generally they grow to around 15â€�-18â€� but fish as large as 2’ have
    been found, if kept in a large enough tank.
  • Water Conditions: Brackish water conditions. Specific gravity around
  • Food: They will eat bloodworms, Cyclops, Tubifex worms, brine shrimps, Daphnia,
    chopped worms, fish and shrimp, and any other similar food. They will also eat
    algae wafers, algae and small sinking pellets of fish food.
  • Recommended Temperature: 73 to 77F, 23 to 25C, a little cooler than most
    tropical fish.


A face only a mother…. or aquarist could love!
Photo by Scott Grahm

Although they are not especially particular about pH, these fish must be kept
in brackish water! This means that you must use marine salt and measure it with
a hydrometer or refractometer.The Dragon Goby’s normal habitat is mud-bottomed areas in river mouths,
estuaries, salt marshes and even the ocean, down to 100ft deep. They may enter
fresh water occasionally but are healthiest in brackish water and that is how
they should be maintained if they are to thrive. Keeping it in freshwater will
compromise its immune system, causing disease and early death. The first Dragon
Goby I had was kept in fresh water (before I knew better). It did live to be 5
years old. At around 2 years, it started to develop pink tumors all over its
body. By 5, it had developed one inside its mouth, until it could not close its
mouth anymore. Since they are filter feeders, they must be able to close their
mouth after gulping in food and water.   ÂNot to be confused with:


These marine gobies are often referred to as “Dragon Gobies”. Amblygobius
semicinctus on the left and Amblygobius sphynx, right. Photos by Robert Fenner

Dragon Gobies are mainly scavengers who put forth only minor effort in
searching for food. Their primary method of obtaining food is by scooping up
mouthfuls of sand and sorting the edible things from the substrate, before
spitting out the substrate and swallowing the food particles. They also use
their lateral “chin fin” to dig around in the muddy bottom. It feeds on
diatoms (the brown “algae” so common in aquariums), various sea algae, small
shrimp and anything else that can fit in its mouth, EXCEPT fish. I have found
that they thrive on Wardley Shrimp Pellets. Mine has been known to suck on an
algae wafer until it gets soft, before gulping it down.

Dragons have tiny eyes and extremely poor vision. They generally hide all day
and come out at night to feed. Since it can’t see or swim very well, the number
one cause of death of these fish is starvation. They should therefore not be
kept with more aggressive eaters, as it often has difficulty finding food
before the other fish in the aquarium have eaten it all. It is best to drop
their food near the opening of their cave, after lights out. Since they have
been observed in the wild to eat continuously, it would be best to measure out
several small feedings throughout the day. Do not overfeed and clean up any
uneaten food. Lacking the swim bladder possessed by normal fish, they are poor
swimmers and “wiggle back and forth” like a snake in the water, or scoot along
the substrate and rocks on their lateral fin. Sometimes you can see them
standing vertically on their pectoral fin, sticking to the glass by their
ventral fin.


A sandy substrate is best for them to dig around in. Sharp rocks can injure the fish. They will create a burrow under or behind a large rock. Being quite shy, dragon gobies like to hide in caves, but the caves need to be small because the fish seem to prefer tight fitting places. PVC pipe will do well also. As a large open cave in full view will simply cause the goby to burrow next to the farthest side, you can trick them by leaning a flat rock against the front glass. They’ll move into their new cave and stay right out front. They will chase out other fish that try to barge in on their territory. With a heavily decorated tank, they will feel secure enough to come out more often during the daytime. However, live plants do not do well in brackish water. You could try java fern or java moss but plastic or silk plants are recommended.

Most aquarium shops and even many books have stated that these fish are fierce predators. Despite its aggressive reputation, it is a very peaceful fish and won’t harm smaller fish. Although they have been known to squabble amongst themselves, it is possible to keep them with conspecifics, as long as there is enough room. Unless a large group can be kept in a tank of about 100 gallons or more, they are best kept singly. In small tanks or small groups, one larger Dragon Goby will dominate the others and some may be bullied or not get enough food. You can keep them with other brackish water gobies, like Bumblebee Gobies or Knight Gobies. It cannot compete with aggressive or boisterous tankmates.

Since these are scaleless fish, Dragons are more prone to skin diseases. They are also more sensitive to medications, so the best preventative against disease is a clean tank. Good filtration and weekly water changes will help keep their water conditions pristine. They must be introduced into a fully cycled tank. If purchased in freshwater, cycle the tank as freshwater and slowly bring the water’s specific gravity up .002/week, until you have reached your desired SG.


Sexual dimorphism of G. broussoneti is distinguished by a small urogenital papilla, which is in the ventral region between the anal opening and the anal fin. In the females it is short, blunt and has a yellow coloration; in males it is thin, pointed and has a smooth appearance. Spawning is possible in a large aquarium. Harper, in Tropical Fish Hobbyist (#473), documents success in captive spawning on pages 130-132. He suggests using a spawning group of one male and three or more females. The tank should be furnished with hiding places for the females and a nest for the male. The fish should not be fed for a week and then conditioned on live foods. The salinity should be lowered and then raised. The male will spawn with several females over the course of a day. Following spawning, the females should be removed and the male will guard the eggs. After 36-48 hours, the fry hatch and the male should be removed. After the egg sacs are consumed, the fry can be fed roftiers and green water containing algae. After a month, Artemia nauplii can be fed. No other spawnings in captivity have been reported. Questions about reproductive seasonality, ovarian development and spawning of G. broussoneti need further investigation.


Note the sandy substrate and plenty of cover. Photo by Scott Graham

This is not a fish for beginner aquarists or even experienced freshwater aquarists beginning in brackish water. A lot of these are sold because of their odd appearance and common names. Who wouldn’t want a purple dragon? But that is insufficient reason to buy a fish and a lot of these animals are kept inadequately, as is the case with most brackish species. Too many aquarium shops tell folks to just “add a little aquarium salt” to make your tank brackish. You need to be dedicated to keep this goby, making sure to keep their water very clean and that they are eating well. If kept properly, this exotic, unusual fish can live close to its teens.

Published by

Jeni Tyrell, AKA Pufferpunk

<img style="float: left;" src="https://img.photobucket.com/albums/v345/Pufferpunk/Bike.jpg" alt="PufferPunk on her Harley" /> <p>It all started when my parents couldn't afford a television, so Mom put me on top of the clean laundry in the basket to watch my Dad's fish. The rest is history! I have been keeping fish for over 27 years now & worked in the industry for about 8.</p> <p>I have had as many as 11 tanks running, ranging from 2g (ghost shrimp gut-loading/snail breeding bowl)-125g (fahaka puffertank). Here is my experience with puffer species, etc:</p> <ul> <li>12" fahaka puffer living in a 125g w/a couple of red-tail & rainbow sharks & 2 very large plecos.</li> <li>2 (6") GSPs a 5" Ceylon. They were in a SW tank w/assorted damselfish, a tomato clown & hermit crabs.</li> <li>5 South American puffers & 1 dwarf puffer living in a 50g w/a frontosa, parrot cichlid & royal pleco.</li> <li>3 F8s living w/knights, bumblebees & a dragon goby.</li> <li>Congo (T. miurus) puffer living in a 15g.</li> <li>10g hex w/a juvenile 2", pignose/arrowhead puffer (T suvattii)</li> <li>20g tank with a 4" T. turgidus.</li> <li>20g w/a 4" A. modestus.</li> <li>A lovely 90g planted tank, w/5 assorted discus, loaches, synodontis, plecos & other oddballs.</li> <li>I have been keeping a 55g reef tank for about 2 years, soon to be upgraded to a 90g & am starting another 50g reef.</li> <li>2 55g river tanks. 1 has assorted toads, treefrogs & African clawed frogs. The other has an dwarf African bullfrog, African sideneck, Asian map & softshell turtle.</li> </ul> <p>(Some of those fish have been re-homed or passed away.)</p> <p>Unfortunately, with all those pets, I recently had to give away all 6 assorted box turtles that had a very nice habitat in the backyard but lived in my basement in a kiddie pool during the winter. I've had some of them for well over 10 years.</p> <p>I own a pufferfish website, The Puffer Forum & am on the Crew of WetWebMedia, in addition to moderating & submitting to countless other forums in the past. I wrote all the puffer fish profiles in the most recent publication of the Encyclopedia of Exotic Tropical Fishes, Published articles on Green Spotted Puffers & Pufferfish Dentistry in Tropical Fish Hobbyist magazine & also in WetWebMedia's online mag, the Conciencious Aquarist, in addition to an article on Dragon Gobies there. </p> <p>I am a scuba diver & underwater photographer. I ride my own 1982 custom Shovelhead Harley-Davidson & am an avid tattoo collector. My Jack Russell Terrier (Kalvin the Krazydog) rides on the back. </p>