Only rarely we can offer the dragon fish, Gobioides broussonnetii, which actually is a species of goby. Now we received once again from Colombia this strange bottom dweller. The maximum length of the species is said to be about 40 cm. They are absolutely peaceful plankton eaters, which should be offered fine sandy substrate in the aquarium.
In the wild, these animals inhabit in large numbers the lower reaches and estuaries of the rivers of the Americas that flow into the western Atlantic Ocean, from the United States to Venezuela. Adults are brackish water fish, while larvae develop in the sea. The species is so common in the wild that it is caught in large numbers as baitfish for other species. In the aquarium they are very adaptable and are quite comfortable in almost pure freshwater. However, for long-term care, we recommend adding sea salt (for coral reef aquariums, not table salt) to the water. A favorable concentration is 5-15g of salt per liter of water. Since the salt content in nature can change abruptly, the fish are insensitive to this, but the filter bacteria react very sensitively to salt fluctuations, so in aquaristic practice one should pay attention to approximately constant conditions.
The huge mouth is frightening, the grim face can only love a mother, but even if it is surprising: these gobies feed in nature mainly vegetarian on algae, namely the microscopic species Coscinodiscus concinus, which is only 150-500 µm in diameter. Just as the giant baleen whales feed on plankton, so do these gobies, and the comparatively large mouth is used to ingest large volumes of water and filter out the tiny algae. Fortunately, however, the fish will eat any common ornamental fish food in the aquarium, and in our tanks Tubifex are very popular as a power food. However, the gobies show the innate suction snapping (whereby water is taken up into the oral cavity) also in the aquarium, only the microparticles in the aquarium water are of course not sufficient for a sufficient nutrition.
All in all Gobioides broussonnetii are very interesting gobies for all who love the unusual!
For our customers: the animals have code 254683 on our stocklist. Please note that we supply exclusively to wholesalers.
Text & photos: Frank Schäfer