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Anonymous
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Well I guess I'll jump into the fray here. I write a regular article for Reef Hobbyist Magazine and I think I'll start adding the text here once it's been published. Here is the article from the current issue about the Japanese or Blue Stripe Cave Goby, Trimma tevegae/caudomaculatum.
The Perfect Nano Reef Fish--Trimma Gobies.
The increasing popularity of nano marine and coral reef aquariums has sparked a concurrent demand for small fish whose lifestyle and size allows them to thrive in tiny tanks of 20 gallons or less. When selecting a fish for a nano aquarium only the smallest of the small will do, and no coral reef fish are smaller than the gobies. Successful stony coral reef aquariums as small as one and two gallons are now almost commonplace among the hobbyist community, and tiny gobies that can thrive in these tanks are now being collected for the aquarium trade. Among the smallest of these are the dwarf gobies of the genus Trimma. There are at least 50 species of gobies in the Trimma genus, and almost certainly many more waiting to be discovered and described. Only a handful of the species that occur in the Western Pacific regularly make it into the US aquarium market. Although they are common, easy to catch, and widespread in the wild, the Trimma gobies were relatively unknown and virtually unavailable for purchase in the US aquarium hobby until early 2004, when dedicated collection began occurring in Cebu in the Phillippines. Since then collection has become more widespread, and at least 5 species are regularly to infrequently available for purchase.
The maximum size for most species is just over one inch! Such a tiny size precludes these gobies from the typical large reef aquarium fllled with large fishes. Large anthias, basslets, cardinalfishes, wrasses, and even tangs will chase down and consume these fish whether they are normally fish predators or not. Large boxer shrimp, hermit crabs, and sea anemones are likewise avoided in the same tanks as these gobies. This does not mean that you can't keep a Trimma goby in anything but a palmtop aquarium, however. Small flasher wrasses, fairy wrasses, dartfishes, damselfishes, shrimp gobies, blennies, dragonets, pygmy angels, pipefish, and other similar species that either consume very small crustaceans or algae will all get along fine with the Trimma gobies, with the caveat that the size differences are not too extreme. It is never a bad idea to add the Trimma gobies to the tank first before any other tankmates. In general these gobies are not very secretive and will hover or rest on the substrate in plain sight as long as they do not feel threatened by larger fish. They do not require a sandy or rubble bottom and so can be kept in bare bottom tanks without concern. There are some unique tank and equipment concerns one must take into account due to their tiny size, mostly to prevent them from being sucked up. The type of propeller (rather than impeller) driven powerheads with large intake strainer holes may be an issue, as well as high flow overflow chambers. The Trimma gobies are adept swimmers but can be sucked up and possibly injured or even killed by such hazards. Ideally the overflow area would be screened off and have a very wide surface area or reduced flow to reduce the intake water velocity.
Once these unique considerations are taken care of, these endearing fishes make wonderful additions to a peaceful community tank. They are hardy and disease resistant and will readily acclimate to an aquarium. Feeding them is simple enough, although it should be done frequently. Trimma gobies may need to be fed small live crustaceans for the first few weeks until they learn to eat flake or frozen food. Live enriched or newly hatched brine shrimp make an ideal food for Trimma gobies. Ideally one would drip in a small supply of baby brine shrimp to the tank during daylight hours, or at least feed the fish several times a day. There are several types of small live and frozen whole marine copepods available through local retailers, and all will make fine food for Trimma gobies. There is, of course, the option of feeding these fish the way nature intended, and a large attached refugium and/or area devoted to culturing copepods and mysid shrimp within the tank will aid in this goal. Once established these fish are not shy about eating flake food, biting off chunks of frozen mysis shrimp intended for other fish, and inspecting just about anything that floats by that might be considered food. The only challenge is to feed them often enough. Inspect the fish on a regular basis to see that it is thick around the midsection and does not have a concave or "pinched in" stomach.
Same or mixed species groups of these fish can easily be maintained in modest sized tanks, although all members of the group should be added at the same time. The most common species available are T. rubromaculatus, T. cana, T. macrophthalma, and T. striata. T. rubromaculatus is perhaps the most commonly available, and sports an irregular pattern of red blotches or polka dots with a white stripe that runs from the nose along the lateral line. T. cana is often called the "Barber Pole" goby with good reason--it has 8 red vertical stripes on a white background. T. macrophthalma and T. striata may sometimes be sold as "Trimma sp." or as an "unidentified goby". Both are generally bright red overall, while T. striata has several radiating dark red stripes on the face and head. The drawback of all the aforementioned species is that they tend to be rather pugnacious with other Trimma gobies. A 10 or 20 gallon tank is suitable for a group of 5-6 of these gobies, but they may initially fight with each other. There are several uncommon species of Trimma which form small schools that hover in the water column rather than rest on the substrate. Only one of these, T. tevegae (also known as T. caudomaculatum), is infrequently available in the aquarium hobby as of this writing. (www.liveaquaria.com has had one of these in their "Diver's Den" section recently.) T. tevegae is commonly called the "Blue Stripe Cave Goby" or "Tail Spot Goby", because it sports three bright blue stripes that run through the eyes and down the back and terminate at a bright purple spot in front of the tail. It is unlikely to be confused with any other Trimma goby.
T. tevegae is less likely to fight with members of its own species and will form small schools in captivity. In at least one Trimma species studied, T. okinawae, sex change has been shown to occur in both directions, meaning that any grouping of gobies placed together may potentially be able to co-exist and reproduce. Eggs are laid on the roof of a small cave and guarded over by the parents. To my knowledge there have not been any successful rearings of Trimma goby larvae in captivity.
