Banded mulletgoby
Hemigobius hoevenii
The Banded mulletgoby features a slender body, distinct dark vertical stripes, and a bluish tint across its scales.
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About the Banded mulletgoby
Neat little mangrove goby that hugs the bottom and hangs around leaf litter. The bold diagonal bars and tail spot look great, and it hunts like a tiny ambush predator, darting out for bites. Keep it gently brackish and it settles in nicely, cruising among roots and wood.
Also known as
Quick Facts
Size
6 cm
Temperament
Semi-aggressive
Difficulty
Intermediate
Min Tank Size
20 gallons
Lifespan
2-5 years
Origin
Southeast Asia and Northern Australia
Diet
Carnivore - small crustaceans and worms; readily takes frozen brine shrimp, mysis, bloodworms, and small sinking foods
Water Parameters
26-29°C
7.8-8.4
12-25 dGH
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This species needs 26-29°C in a 20 gallon tank. Use our heater calculator to find the right wattage.
Calculate heater sizeCare Notes
- Run them brackish at SG 1.008-1.015 with a marine salt mix; keep pH 7.6-8.2, 24-28 C, and top off evaporation with freshwater only so salinity does not creep up.
- If the shop had it in freshwater, step salinity up over 1-2 weeks by raising SG 0.002-0.003 per water change.
- Give a 20-30 gallon tank with fine sand and lots of hides - half-buried PVC elbows, rock caves, or mangrove roots - and gentle to moderate flow.
- Use a tight lid; they launch when spooked.
- Feed meaty foods that sink or can be target-fed: frozen mysis, brine, chopped prawn, bloodworms, and small carnivore pellets; use a turkey baster so faster fish do not steal it.
- Tankmates: medium brackish fish like robust mollies or similar-sized gobies work; skip tiny bumblebee gobies and shrimp (they are snacks) and avoid big bullies like monos, scats, or large archerfish.
- They get about 8-10 cm and can be semi-territorial on the bottom; keep one male or add extra caves and break sightlines if you want a group.
- Wild-caught often carry worms, so a praziquantel round is worth doing; if you see heavy breathing, check nitrite and bump aeration.
- Breeding is cave-based with the male guarding eggs, but the larvae go pelagic and need marine water and live plankton, so raising fry at home is a hard project.
Compatibility
Good Tankmates
- Brackish-tolerant livebearers like mollies (sailfin, black) and hardy guppies that cruise mid-top and do not hassle the goby
- Schooling Indian glassfish that stick to midwater and leave the goby to guard the sand
- Top-dwelling halfbeaks (Dermogenys/Wrestling halfbeaks) that are quick and ignore bottom territories
- Orange chromide cichlids if you give them space and cover; similar salinity and attitude without steamrolling the goby
- Another robust brackish goby like a knight goby, but only with lots of rock/driftwood to break sight lines and not too many males
Avoid
- Puffers like figure 8 or green spotted that nip and will worry a goby to death
- Big boisterous brackish cruisers like scats, monos, archerfish, or Colombian sharks that outcompete or swallow smaller bottom fish
- Tiny nanos like bumblebee gobies that get outcompeted at feeding time and bullied off the sand
- Ambush predators and sleeper gobies like Butis butis that will snack on smaller fish hanging near the bottom
Where they come from
Banded mulletgobies show up all over Indo-West Pacific estuaries and mangroves. Think silty creeks, tidal flats, and the lower ends of rivers where salinity swings with the tide. They spend their days nosing around sand and mud for tiny critters, ducking into roots and shells when startled.
- Adult size: about 7-8 cm
- Water: brackish to near-marine, very tolerant of swings (within reason)
- Lifespan: 3-5 years with steady conditions
Setting up their tank
They are not fussy about decor, but they do care about salinity, sand, and having lots of hidey-holes. A tight lid is non-negotiable. They jump when spooked.
- Tank size: 20 gallons minimum for a small group, bigger footprint beats height.
- Substrate: fine sand. They pick at it and like to settle without scraping their bellies.
- Hides: short sections of PVC, small caves, cockle or clam shells, driftwood, and fake mangrove roots. Break up line of sight.
- Salinity: SG 1.005-1.015 is a sweet spot. They handle up to 1.020, but mid-brackish is easiest day-to-day.
- Temp: 24-28 C (75-82 F).
- pH and hardness: pH 7.5-8.2, moderate-hard water keeps them perky.
- Flow and filtration: moderate flow with good surface agitation. They appreciate oxygen-rich water.
- Lighting: subdued or dappled. Bright tanks are fine if you stack cover near the bottom.
- Plants: low-end brackish picks like Java fern, Anubias, and Vallisneria can work. Mangrove seedlings are great if you are into that.
Use a marine salt mix, not table salt or freshwater aquarium salt. Top off evaporated water with freshwater only so salinity does not creep up.
Cycle the tank at the target salinity from day one. A refractometer is more accurate than a swing-arm hydrometer and saves you guesswork.
What to feed them
They are micro-predators. Mine took to frozen foods quickly and learned pellets after a couple of weeks. They hunt the bottom, so get the food down to them instead of letting it spin around at the surface.
- Frozen: mysis, brine shrimp (enriched), chopped krill, bloodworms (use sparingly).
- Live if you can: blackworms, daphnia, copepods. Great for getting new fish eating.
- Dry: small sinking carnivore pellets or granules. Mix with frozen at first so they recognize it as food.
- Schedule: 1-2 small meals per day. Watch bellies; a slight curve is fine, ballooning means you are overdoing it.
Target feed with a pipette or turkey baster into their caves and along the sand. It keeps bolder fish from stealing everything.
How they behave and who they get along with
Calm most of the time, with little sprint-chases to remind neighbors who owns which shell. Males posture more. In a tank with enough cover, scuffles are brief.
- Best kept as: one male with two or more females, or a small group in a larger tank with many hides.
- Good tankmates: mollies, orange chromides, peaceful glassfish, peaceful sleepers/other mild gobies, nerite snails.
- Borderline: knight gobies can be pushy; works only in larger tanks with lots of cover.
- Skip: figure eight puffers, archerfish, scats/monos (too big and boisterous), large cichlids, shrimp (they are snacks).
Add the gobies before or at the same time as other bottom fish. If you add them last, established fish may box them out of caves and food.
Breeding tips
They will court and lay eggs in a cave in home tanks, but raising the young is the tricky part. The male guards the eggs; once they hatch, the larvae go pelagic and usually need near-marine water and microscopic foods.
- Condition the pair/group with heavy live and frozen foods.
- Offer multiple tight caves: short PVC elbows, shells, or small pots turned on their side.
- Keep salinity around SG 1.010 for spawning. The male fans and guards the clutch.
- Eggs typically hatch in 3-6 days depending on temperature.
- To attempt rearing: move the cave to a larval tank at SG 1.015-1.020, gentle light, bare bottom, and constant fine aeration near (not on) the eggs.
- First foods: rotifers and greenwater, then newly hatched brine shrimp once the larvae are big enough. Frequent small feedings and spotless water are key.
Most hobbyists let the adults spawn as enrichment and do not try to raise the larvae. If you do try, be ready for a marine-style larval setup and expect a learning curve.
Common problems to watch for
- Jumping: they launch through cable gaps. Tight lid, foam in cutouts.
- Salinity creep: evaporation raises SG. Mark your waterline and top off daily with freshwater. Re-check with a refractometer weekly.
- Using the wrong salt: only reef/marine mix gives the minerals they need. Plain aquarium salt is not enough.
- Food hogging by tankmates: target feed and spread food across several spots.
- Internal parasites or worms: new fish that stay thin despite eating often have them. Quarantine and deworm with an appropriate medication at brackish SG.
- Bickering: too few hides or too small a footprint. Add more caves and line-of-sight breaks.
- Fin nips and fungus: usually from bad tankmate choices or stress. Swap out bullies and bump water quality with extra water changes.
- Ich and velvet: less common in brackish but possible. Treat in a hospital tank so you can medicate at the right salinity without nuking the display.
If they go off food suddenly, test everything: ammonia, nitrite, nitrate, SG, temp, pH. In brackish tanks, a quiet salinity swing after a big evaporation or water change is a classic appetite killer.
Similar Species
Other brackish semi-aggressive species you might be interested in.
Banded Archerfish
Toxotes jaculatrix
This is the fish that literally spits jets of water to knock insects off branches-watching one "take aim" is unreal. They're super aware of what's going on outside the tank and will even learn to beg and snipe food from the surface once they settle in. Give them height and some open swimming room and they act like little aquatic sharpshooters.
Barred mudskipper
Periophthalmus argentilineatus
This is one of those classic "walks around like it owns the place" mudskippers-big goofy eyes, climbs, hops, and spends a ton of time out on the mud when it's humid. In the wild it lives on intertidal mangrove/nipa mudflats and even shuttles between little pools and open air, hunting worms, insects, and small crustaceans. It's super fun to watch, but it really wants a brackish paludarium setup (not a normal aquarium).
Bellfish
Johnius fuscolineatus
Johnius fuscolineatus (Bellfish/African bearded croaker) is a small coastal sciaenid from the southwestern/western Indian Ocean (Mozambique, South Africa, Madagascar), occurring in shallow marine waters (reported 0–50 m) and also associated with coastal/estuarine habitats.
Blotched eelpout
Zoarces gillii
Zoarces gillii is a cold-temperate eelpout from the Northwest Pacific that hugs the bottom over sandy-mud inshore areas and even pushes into estuaries. It's got that long, eel-like body and a sneaky, sit-on-the-bottom predator vibe - very much a cool-water, brackish-to-marine oddball rather than a typical tropical aquarium fish.
Bumblebee goby
Brachygobius doriae
Brachygobius doriae is one of the classic "bumblebee gobies" - tiny, bottom-hugging little characters that perch on rocks and sand and stare at you like they own the place. They're at their best in a calm setup with lots of caves and leaf litter, and they really shine once you get them eating frozen/live foods reliably (they're slow, picky eaters). Also: they're one of the species that gets mislabeled a lot in shops, so it's super common to see them sold under the wrong bumblebee-goby name.
Bumblebee goby (Bumblebee fish)
Brachygobius xanthozonus
This is that tiny little goby with the bold black-and-yellow bands that likes to perch on the bottom and stare back at you like it owns the place. It's happiest in lightly brackish water with lots of little caves and sight-breaks, and it's one of those fish that often refuses flakes-frozen/live meaty foods usually flip the "yes, I will eat" switch.
More to Explore
Discover more brackish species.
African moony
Monodactylus sebae
This is that shiny, diamond-shaped "mono" that cruises around in a tight pack and looks like a little silver dinner plate with black bars when it's young. The big thing with African moonies is they're euryhaline-so they'll tolerate freshwater as juveniles, but they really shine long-term in brackish (and can be transitioned toward marine as they mature). Give them a big, open tank and a group, and they turn into nonstop, super fun midwater swimmers.
American shadow goby
Quietula y-cauda
This is a little mudflat goby from California down into the Gulf of California that loves hanging tight to the bottom and vanishing into burrows. The neat tell is that sideways Y-shaped blotch right at the base of the tail, plus the row of dark spots along the side. Its whole vibe is brackish estuary life - calm water, soft substrate, lots of hiding holes.
Atlantic Mudskipper
Periophthalmus barbarus
This is that wild little amphibious goby that straight-up climbs around on land like it forgot it was a fish. They've got big googly eyes, tons of personality, and they'll perch, hop, and patrol their territory-honestly more like a tiny crabby lizard than a "regular" aquarium fish.
Banded-tail glassy perchlet
Ambassis urotaenia
This is one of those see-through glassy perchlets where you can literally watch the organs shimmer when it turns-super cool in the right lighting. In the wild it hangs around river mouths and mangroves and cruises in groups, so it does best when you keep a little gang of them and give them some open swimming room.
Barbed pipefish
Urocampus nanus
Urocampus nanus (barbed pipefish) occurs in protected inshore and estuarine habitats among seagrass (Zostera) in the Northwest Pacific (southern Japan and adjacent coasts). Like other syngnathids, males brood eggs in a pouch under the tail and produce fully formed young.
Beach silverside
Atherinella blackburni
This is a little coastal silverside that cruises the shallows in loose groups and flashes like a tiny chrome dart when the light hits it right. In the wild it hangs around beaches, estuaries, and lagoons, picking at small drifting foods in the surf zone. It is cool, but its real "gotcha" is that it is an open-water, salt-tolerant schooling fish that does best in bigger, well-oxygenated setups rather than a typical planted community tank.
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