Gobies in general are underappreciated and often thought of as bland bottom dwellers. But the Firefish Goby turns this myth right on its head! In fact, it’s one of my favorite fish to recommend to first time marine aquarists. They are active, striking, peaceful, and easy to keep, with few downsides besides being intolerant of other Firefish. Interested yet? Let’s see what else Firefish Gobies have to offer!
About Firefish (Fire Goby)
The common name “Goby” is a little problematic in the aquarium world because it gets thrown around way too readily. A fish with the common name “Goby” is basically a squat, bottom dwelling fish that may or may not be related to other squat, bottom dwelling fish that are also called Gobies.
Some prime examples of Gobies that aren’t true Gobies include Engineer gobies and Mandarin gobies. But don’t let their lack of goby-ness disappoint you; these fish still have plenty to offer!
As members of the family Gobiidae, Firefish are true Gobies! And like all gobies they are small in stature and spend a lot of their time squabbling with one another. But their active disposition, brilliant colors, and ease of care makes them popular fish among aquarists of all skill levels.
The bold blue tones in their eyes, and gentle transition from fiery red to creamy white helps them stand out in tanks. And their dorsal fins act like little flags, signalling their moods and intentions to one another.
Firefish are found across a wide swath of ocean, from the East African Indian Ocean, all the way to the island archipelagos of the Pacific, even as far east as Hawaii! This makes them a fixture on nearly any IndoPacific reef you’ll come across. And while they are mostly wild-caught they are so common that there is thankfully minimal impact on wild populations.
Firefish eat heartily and are entirely peaceful towards their tank mates, to the point of being somewhat shy and skittish in certain conditions. What else is there to know about Firefish and how can we make sure ours live long and happy lives?
- Common Names: Firefish, Fire Goby, Red Fire Goby, Fire Dartfish, Magnificent Dartfish
- Scientific Name: Nemateleotris magnifica
- Origin: IndoPacific Ocean
- Length: 3 inches
- Aquarium Size: 10 gallons
- Temperament: Peaceful
- Ease of Care: Very Easy
Firefish Goby Care
Peaceful, hardy, inexpensive, and attractive, the Firefish Goby is an ideal first fish for aquarists of all skill levels!
Aquarium Size
Firefish are small to the point of being nano fish. When small, they can thrive in tanks as small as 5 gallons! But as they grow larger, they really should be kept in at least 10 gallons of space. They get to be 3 inches long when fully grown, which is just a bit too large for a 5 gallon nano tank.
Firefish are also quite active, though they tend to concentrate their activity around a particular favorite bolt hole that they can retreat to. Even when they have holes all around the tank to choose from, your Firefish Goby will likely choose a single hole as his permanent home.
This is due to their conditioning in the wild: Firefish live in communities of several dozen fish. A good hiding spot is crucial for their safety and success so they compete intensely for them. Even if your Goby lives alone it will likely prefer sticking to a single home.
If you want to keep more than one Firefish Goby, you should provide 10 gallons of space per Goby. You should also introduce each of them to the tank at the same time. If there are already one or more Firefish that are established and have territories, the newcomers will be relentlessly chased in all but the largest of tanks (55+ gallons).
By adding them all at once, the Firefish start out on equal footing and will set up a pecking order and find favorable hiding places to suit them. Just make sure that your live rock aquascaping can support their territorial nature; don’t cluster all of the hiding space near one another in case you get two males.
Firefish can’t be sexed by humans visually so there’s a certain degree of luck involved in keeping these fish in pairs or groups.
Water Conditions
Firefish are very hardy and undemanding. They prefer the standard water conditions that apply to the majority of fish-only marine tanks. This means a pH of 8.0-8.4, temperatures of 72-80℉, and a specific gravity (salinity) of 1.020-1.025.
In fact, you’re safe adding a Firefish as one of your first aquarium inhabitants. They tolerate shifts in water parameters well and the slightly elevated ammonia, nitrite, and nitrate levels that come with New Tank Syndrome are unlikely to harm them.
That said, we should still always seek to keep ammonia, nitrite, and nitrate as close to 0 ppm as possible in fish-only tanks. Corals, especially the more beginner-friendly soft corals, enjoy tiny amounts of nitrate (1-10 ppm) as it fertilizes their zooxanthellae. Otherwise, nitrate is a pollutant that we want to ensure our biological filtration system eradicates!
In fish-only tanks, we also don’t need to pay too much attention to calcium, strontium, magnesium, and other elements found in seawater. Firefish and other marine fish to absorb some of these agents. But there is more than enough found in high quality marine salt to meet their needs, unlike corals, which often need supplementation to fuel their growth.
Are Firefish Gobies Reef Safe?
Firefish Gobies are some of the best reef fish you can buy! Delightfully colored, peaceful, and too small to harm even the smallest shrimp, they will do no harm to your corals, Feather Duster worms, or other sessile invertebrates. Many of the best tank mates for Firefish are also reef safe, including Mandarin Gobies and Clownfish!
Firefish also won’t harm Starfish, hermit crabs, sea urchins, brittle starfish, and the other inhabitants of most reef aquariums. Nor are they rough on corals and anemones like hosting Clownfish tend to be.
Tank Mates for Firefish Gobies
Choosing tank mates for your Firefish Goby can be easy or difficult, depending on what sort of fish you like. Firefish are very peaceful and can live alongside just about any fish. However, in certain conditions, they can be shy to the point of being skittish, and the wrong tank mates can definitely bring this out in them.
Semi-aggressive and aggressive community fish like larger Clownfish, Damselfish, Dottybacks, and even some Pygmy Angelfish should be avoided. Royal Grammas, Royal Dottybacks, and other similarly light/dark bicolored fish are a risk because all of these are likely much more aggressive than the Firefish and will chase it at any opportunity.
Smaller, peaceful community residents include the Cherub Angelfish (Centropyge argi), the True Percula Clownfish (Amphiprion percula), the Yellow Tang (Zebrasoma flavescens), the Yellowtail Blue Damselfish (Chrysiptera parasema), Mandarin Gobies, and Blennies of all kinds! Firefish also live peacefully with both small and large saltwater shrimp of all kinds, clams, snails, corals, sea anemones, and other invertebrates. Predatory tank mates, like Lionfish, Groupers, and Moray Eels, should obviously be avoided.
Keeping them with each other is the only real challenge because they can be aggressive to the point of the loser being stressed to death. Even other Firefish, such as the Purple Firefish (Nemateleotris decora) or Exquisite Firefish (Nemateleotris exquisita) may be too similar for your Firefish Goby to tolerate.
The best way to keep multiples is to introduce them all to the tank at the same time. That way, each Firefish is starting from a clean slate. They will squabble a little but don’t have established territories to defend yet. They will figure out an arrangement that best suits them and is stable over the long-term!
Feeding Firefish Gobies
Firefish Gobies are thankfully very easy to keep fed. As reef micro predators they are carnivorous, feeding mostly on the zooplankton that wafts over the reefs. However they adapt well to captive life and accept appropriately sized flake and pellet based foods.
You can supplement this with fresh and frozen items like brine shrimp, copepods, and other tiny invertebrates. Offering a mixture of live, fresh, and frozen foods is by far the best way to condition your Firefish to spawn as well!
Breeding Firefish Gobies
The only difficult aspect to keeping Firefish Gobies is breeding them. Due to their intolerance for each other and our inability to tell the sexes apart, it’s difficult to get a mated pair. And even if you have a pair, they don’t spawn very often in captivity.
That said, it does happen occasionally! Usually, a lucky aquarist gets a hold of a wild pair that’s already mated or that have bonded in captivity. Or, they introduce 2 or more Firefish to a tank at once and they end up being compatible with one another.
As I mentioned above, the best way to get multiple Firefish to coexist peacefully is to introduce several of them to the tank all at once. Once established, your Firefish will be able to tell each other apart by sex and will pair off if compatible. Firefish mate for life in stable, monogamous pair bonds so it pays to be picky in this regard!
Since we can’t visibly tell them apart it’s likely Firefish use hormonal and behavioral cues to figure out the sex of anotehr fish. They may even change sex based on social dynamics, which is very common among marine fish, but as of yet that’s unknown in this Goby.
The few times they’ve spawned in captivity, the Firefish Gobies will lay their eggs in a small crevice or cave near their preferred hiding places. The pair then watches over the eggs, though in a gentle manner suiting such small, peaceful fish.
Reports where an aggressive crustacean or fish decided to eat the eggs show that Firefish refuse to attack intruders even at this point. They merely hover around the general vicinity of their eggs, subtly “discouraging” trespassers but not actively chasing them away.
The young fry are almost certainly planktonic when born. Meaning they float away to join the zooplankton currents of the reef. Once the young Firefish fry grow large enough, they swim down to the bottom and find holes to defend, repeating the cycle.
Fish with a planktonic phase are difficult to rear in home aquariums because the fry are too likely to get sucked up into the filter or protein skimmer. If you find Firefish eggs, your best bet is to move them to a separate rearing tank set up with a gentle sponge filter. There, you can provide a steady soup of live infusoria (microscopic organisms) to feed the tiny Firefish until they grow large enough to eat brine shrimp nauplii and other more standard fare!