Zebra goby

Where they come from

Zebra gobies (Zebrus zebrus) are a Mediterranean and Black Sea fish. You usually find them in shallow rocky zones, tidepools, and crevices where the water stays on the cooler side. They spend a lot of time wedged in cracks, peeking out and dashing for snacks. That bold stripe pattern makes perfect sense once you see them against a jumble of rocks and shadows.

Setting up their tank

They do great in a rock-heavy scape with tons of tight caves. Think rubble piles, stacked rock with little slots, and a few shady overhangs. A single zebra goby is comfy in 20 gallons; for two, I like 30+ with multiple hide zones so nobody gets boxed in.

• Temperature: 16-22 C (60-72 F). Stability beats chasing exact numbers.
• Salinity: 1.023-1.026. pH 8.0-8.4, alkalinity 7-10 dKH.
• Flow: moderate with slack spots behind rocks. They appreciate calm pockets.
• Light: low to moderate. They relax in shaded areas.
• Substrate: fine sand or mixed grain is fine. They perch more than dig.
• Cover: tight lid or 1/8 in mesh. Gobies can and will jump.
• Filtration: normal marine filtration works. Add extra aeration if you keep the tank on the cooler end.
• Refugium or pod-rich rock helps a ton while they settle in.
• Guard powerhead intakes with foam or mesh so they do not get pinned.

Acclimate slowly and keep the lights dim for the first day or two. I usually shut off the room lights, add a small feeding dish near their chosen cave, and let them learn the routine without pressure.

What to feed them

They are micro-predators that pick at tiny crustaceans and worms in the rocks. New arrivals can be shy about eating in open water, so target feeding near their cave works best.

• Frozen mysis (small or chopped) - my most consistent starter.
• Vitamin-enriched brine shrimp - use as a bridge food, not the only thing.
• Calanus or copepod concentrates - good scent and size.
• Finely chopped prawn, clam, or squid.
• Live options: enriched adult brine, live blackworms (rinsed), or copepods to spark feeding response.
• Use a pipette or feeding stick to deliver food right to the cave entrance.

Feed small portions 1-2 times a day. If tankmates are faster, distract them on one side of the tank and feed the goby on the other. Soaking foods in a vitamin mix a couple times a week helps, especially while they settle.

How they behave and who they get along with

Zebra gobies are cave sitters and quick dashers. They will pick a little territory and guard it with attitude, but they are not bullies if they have cover and line of sight breaks. Expect them to watch you from the shadows at first and then get bolder once they link you to food.

• Keep one per tank unless you have a big setup with tons of hides. A compatible pair can work, but two random adults may fight.
• Tankmates: other small, calm fish that handle cool water. Avoid aggressive dottybacks, damsels, hawkfish, and big wrasses.
• Inverts: they ignore snails and larger hermits. Super tiny shrimp could be viewed as snacks, so pick sturdier inverts for a temperate setup.

Breeding tips

They are cave spawners. The female lays eggs in a tight cavity, and the male guards and fans them. Getting a true pair is the tricky part; sexing is subtle and not well documented, so most people let two youngsters sort it out in a roomy tank.

• Offer nest sites: short PVC stubs, empty shells, or narrow rock slots.
• Condition with frequent small feedings and cool, clean water. Slight seasonal cooling followed by a gradual warm-up within the 16-22 C range can help.
• If they spawn, eggs will be on the roof of a cave. Hatching leads to tiny planktonic larvae.
• Larval rearing is advanced: separate kreisel or round larval tank, greenwater, rotifers enriched with algae paste, then newly hatched Artemia. Gentle light and very mild aeration.

Common problems to watch for

• Heat stress: fast breathing, surface hanging, going off food. Fix by cooling the tank gradually.
• Jumping: tight lid always. They bolt during spats or night frights.
• Refusing food: target feed small, smelly items near the cave and keep tankmates from stealing everything.
• Aggression from tankmates: if they never leave the cave, rethink the stocking list.
• Parasites: ich and velvet are still possible in temperate systems. Quarantine new fish 2-4 weeks.
• Low oxygen: cool water holds more O2, but still keep decent surface agitation, especially if you pack in rock.

Quarantine pays off with this species. A quiet QT with some PVC caves lets you fatten them up and confirm they are eating frozen foods before they face competition in the display.