Family Gobiidae - The Gobies
There are at least six different families in the suborder Gobioidei with close to three hundred genera and over 2,000 species described to date. Most are tropical marine fish, live on the bottom and are very small (one of the world’s smallest fish, Trimmatom nanus, is from the family Gobiidae, although the smallest described species in from the family Schindleriidae). Gobies are personable and interesting to watch, especially those species that live in symbiotic relationships with invertebrates. Most are territorial, although keeping pairs or small groupings in an aquarium are appropriate for some species. Generally they are elongate with blunt heads and high-set eyes—somewhat blenny-like. Gobies can readily be differentiated from blennies, however, by their dorsal fin—many gobies have two, blennies only have one. Also gobies have pelvic fins that are fused to create a sort of suction cup apparatus. One note of caution when choosing a goby, beware that there are many fish sold as gobies that are not gobies at all. Most notably, the dragonets are often sold under the common name goby, but they are not actually gobies, and their requirements are really quite different.
The favorites in the hobby from the family Gobiidae are generally considered to be 1) the goby-shrimp symbionts, 2) the so-called clown gobies, and 3) the neon or cleaner gobies. All of the species discussed here, given the right environment and diet, can do quite well in the home aquarium. While there are certainly other gobies to consider, this is too large a family to deal with comprehensively in a short article. The aquarist who decides to explore beyond the species in the genera mentioned here should make sure 1) that the goby is actually a goby instead a fish that is only nominally a goby, and 2) to do his or her homework regarding habitat requirements and dietary needs for the specific fish being considered.
Symbiont Gobies from the Genera Amblyeleotris, Cryptocentrus and Stonogobius
Many people have a goby-shrimp symbiont pair as the centerpiece of their aquarium, and most agree this can be one of the more interesting displays in the hobby (right up there with the clownfish-anemone display). While many gobies will establish symbiotic relationships with a variety of invertebrates ranging from urchins to sponges, the goby-shrimp symbiont species in the genera Amblyeleotris, Cryptocentrus and Stonogobius are among the best known and most readily available in the hobby.
There are 13 species of digging gobies from the genus Amblyeleotris, and many of them make excellent additions to the home aquarium so long as that aquarium is well-established, has a sandbed of at least two inches and, preferably, has a refugium as part of the overall system. These gobies eat continually in the wild, and they do best in an aquarium with well-established populations of pods and filamentous algae. The most common cause of captive losses is starvation. All tanks with gobies should be covered, as all gobies are prone to jumping to their death. Most will adapt to a captive diet of meaty foods including frozen mysis shrimp, raw table shrimp and other commercially prepared frozen foods, pellets and flakes. A real favorite of this genus is the Randall’s Shrimp Goby (A. randalli), which is one of the fanciest in the entire goby family. It is an excellent aquarium fish, especially if paired with a Pistol Shrimp from the genus Alpheus.
The genus Cryptocentrus is made up of 22 species including the colorful and personable Bluespotted Watchman Goby (Cryptocentrus pavoninoides). This fish has two color phases—one being the more popular orange with blue spots and the other being a drab albeit still attractive) olive with blue spots. The Bluespotted Watchman Goby pairs easily with Pistol Shrimp in a well-established system with at least a two-inch sand bed.
As great as both the Randall’s Shrimp Goby and Bluespotted Watchman Goby are, the Yasha Hase Shrimp Goby (Stonogobiops yashia) has become a real darling for hobbyists seeking a goby-shrimp pair. A relatively recent addition to the hobby, the Yasha Hase Shrimp Goby makes a stunning display with its red and white stripes and yellow tail. When paired up with a Randall’s Pistol Shrimp (Alpheus randalli), it make a very attractive symbiotic display. This is a more difficult fish to keep than either the Randall’s Shrimp Goby or the Bluespotted Watchman Goby and needs to be acclimated slowly. In addition, the Yasha Hase Shrimp Goby may be difficult to acclimate to a captive diet. Adult Yasha Hase gobies prefer to live in pairs, and they are known to live peacefully with other non-aggressive tankmates (although they may become slightly aggressive during feeding).
Clown Gobies of the Genus Gobiodon
The clown gobies of the genus Gobiodon make excellent reef aquarium specimens, especially because of a unique noxious body slime that makes them less palatable to more aggressive reef fish that would normally eat a fish this size. There are 13 species in the genus Gobiodon from which to choose, but the favorites are the Citron Clown Goby (G. citrinus) and the Green Clown Goby (G. histrio). Both of these fish do well in a reef aquarium, and both their color and behavior make them a joy to observe. Species in the genus are hermaphrodites and readily form pairs and spawn in captivity. While they are generally considered reef safe, caution should be observed when placing these fish in a reef environment as they prefer to perch on stony corals, and this frequently stresses the coral. In addition, pairs are known to tear the skin off stony corals to make a nest.
The Cleaner Gobies of the Genus Gobiosoma
Perhaps the most “useful” gobies are those from the genus Gobiosoma—the neon or cleaner gobies—which are as attractive as they are hardy. They also serve as cleaner fish, happen to be fantastic captive breeders and have great personalities. The Blue Stripe Neon Goby (G. oceanops), for example, has an amazing personality for its size and will readily nip cysts off of other fish. In smaller tanks, Blue Stripe Neon Gobies may fight amongst each other, but a mated pair in a larger tank will readily spawn and ferociously protect their eggs. Neon gobies make a great addition to an aquarium with large polyp stony corals, and will gladly eat anything fed to the other carnivores in the tank. They especially enjoy mysis shrimp, raw table shrimp, flake, pellet, and other meaty foods.
Most gobies appreciate a tank that is well aquascaped for their specific needs. In the wild, they inhabit a variety of habitats from shallow beach environments and muddy grassflats to coral reefs and the ocean bottom. All gobies need a refuge, usually a hole they dig in the substrate, a host invertebrate such as a sponge, or simply a crevice in the rockwork. Many species require a sandbed, but some will be most at home when perched in the delicate branches of gorgonians. Gobies generally do well in both community fish-only tanks and reef tanks (although it should be cautioned that some may inevitably become snack food for larger fish). They generally possess a peaceful disposition, although they can be quite territorial with fish of their own species. Most gobies prefer good water quality. Some species, like the Yellow Goby (Gobiodon Okinawae), will actually lose their bright coloring if water quality becomes poor. Standard marine biological/mechanical filtration is recommended.
Gobies vary somewhat in their diet, so once again, it is essential to research the individual species. Many do quite well on a standard captive diet, while others are more difficult to wean onto prepared foods. As a rule, gobies are carnivores and will eat small pieces of marine flesh, frozen foods and flake food. Some will only eat live food during the acclimatization process and should only be introduced to an established tank (and preferably one with a refugium connected) with a healthy pod population.
Species in the family gobidae are fairly disease resistant, which is a good thing since they do not fare at all well with many of the standard treatments (e.g. medications containing copper, malachite and formalin). Unfortunately gobies tend to be short-lived (a year or two for many).
While one Leviathan species from the family Gobiidae can reach eighteen inches, the vast majority of gobies are small (under four inches), and many are well-suited for the home aquarium. They are personable, reasonably hearty and extraordinarily interesting behaviorally. They can do well in small aquariums or large reef aquariums, and beyond their aesthetic value, some gobies perform useful tasks like cleaning other fish and protecting invertebrates. It is important to remember that this is a huge family, and this article only scratches the surface by discussing some generalities about species in the family and highlighting a few of the favorites in the hobby. As with all fish, the hobbyist considering a goby must do his or her species-specific research in order to maximize the chances of long term success, but generally speaking a goby is an outstanding addition to the home marine aquarium.