Peacock gudgeon
Tateurndina ocellicauda
Also known as: Peacock goby
Peacock gudgeons are little jewel-fish from eastern Papua New Guinea with that awesome "eye spot" on the tail and a ton of blue/yellow/red speckling. They're gentle most of the time, but the males get pretty into cave/crevice territory when they're thinking about spawning-and watching the male guard and fan eggs is seriously cool.
Peacock gudgeons exhibit vibrant blue-green and gold coloration, with striking tail patterns marked by red and yellow spots.
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Quick Facts
Size
7.5 cm (about 3.0 inches)
Temperament
Peaceful
Difficulty
Beginner
Min Tank Size
15 gallons
Lifespan
4-5 years
Origin
Oceania (eastern Papua New Guinea)
Diet
Micropredator/omnivore leaning carnivore – small frozen/live foods (brine shrimp, daphnia, bloodworms) plus quality micro-pellets/flakes
Water Parameters
22-27°C
6-7.8
5-12 dGH
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Calculate heater sizeCare Notes
- Give them a planted tank with lots of little hideouts (rocks, driftwood, leaf litter) and especially a small cave like a coconut shell or short bit of PVC-those caves make them feel secure and also double as spawning spots.
- They're pretty chill on freshwater, but they look their best around 74-79°F (23-26°C), pH roughly 6.5-7.5, and they hate big swings-keep ammonia/nitrite at 0 and don't let nitrate creep way up.
- Flow-wise, think "gentle": a sponge filter or a baffled HOB works great; strong current tends to make them skittish and they'll hang back instead of cruising.
- Feed small meaty foods and mix it up-frozen brine shrimp, daphnia, bloodworms, and live foods get the best response; many will take micro pellets, but don't be shocked if they ignore dry food at first.
- They're slow, picky eaters, so in a community tank make sure they actually get food-target feed with a pipette/turkey baster if faster fish are stealing everything.
- Good tankmates are peaceful small fish like rasboras, ember/neon tetras, and corys; skip fin-nippers (serpaes, some barbs) and anything big enough to think "snack," and avoid mixing with super pushy feeders.
- Breeding is fun and pretty easy: a pair will lay eggs in a cave, the male guards them, and you can pull the cave to a small rearing tank if you want more fry to survive; the fry do best starting on infusoria/microworms then baby brine shrimp.
- Watch for two common issues: they can come in skinny with internal parasites (quarantine and treat if they won't put on weight), and they're prone to getting outcompeted-if yours hides all day, it's usually tankmate/flow/feeding pressure, not "mystery disease."
Compatibility
Good Tankmates
- Small, chill schooling fish like ember tetras, rummynose tetras, or glowlight tetras - they stay midwater, don't bother the gudgeons, and it keeps the tank feeling busy without stressing anyone out.
- Corydoras (pygmy, panda, pepper, etc.) - peaceful little floor crew. Peacock gudgeons mostly ignore them, and they don't compete much for territory.
- Otocinclus - great if your tank's mature. They're super non-pushy, stick to their algae business, and gudgeons don't see them as rivals.
- Small rasboras like harlequins or chili rasboras - calm, easygoing, and they're quick enough at feeding time that the gudgeons don't get outcompeted too badly.
- Bristlenose pleco (or other smaller, peaceful plecos) - works fine in most setups as long as you've got hiding spots. They occupy different real estate than the gudgeons.
- Peaceful dwarf shrimp (cherry/neos) *may* work with heavy cover, but expect losses (especially shrimplets) and monitor closely.
- Warning: Very fast feeders (e.g., danios) can outcompete them at meals; if mixed, plan on target feeding and observe body condition.
Avoid
- Anything nippy like tiger barbs or many fin-nippy "busy" barbs - gudgeons are mellow and can get stressed and chased, plus they won't compete well long-term.
- Big or bossy fish (most cichlids, larger gouramis, anything that wants to own the whole tank) - peacock gudgeons are peaceful but the males can be territorial, and they lose every argument with bigger attitude.
- Crayfish and larger predatory inverts - they're grabby at night and will absolutely take a shot at a resting gudgeon (or just stress them into hiding).
1) Where they come from
Peacock gudgeons (Tateurndina ocellicauda) come from Papua New Guinea—slow streams and swampy edges with plants, leaf litter, and lots of little hidey-holes. That vibe (gentle flow, cover everywhere, snacks drifting by) is basically the secret recipe for keeping them happy in a tank.
2) Setting up their tank
These are small fish, but they act like they own the place once they settle in. A 10–20 gallon works great for a small group, and they really appreciate structure—wood, rocks, plants, and caves to break up sightlines.
- Tank size: 10 gal for a pair/trio, 15–20 gal for a group (I like 20 long if you can swing it)
- Temp: mid-70s°F (around 74–78°F is a comfy zone in my tanks)
- pH/hardness: they’re pretty flexible; aim for “normal community tank” water and keep it steady
- Filter: sponge filter or a gentle HOB—moderate flow is fine, blasting current isn’t
- Decor: caves/tubes/coconut huts + plants (Java fern, Anubias, Crypts) + a bit of leaf litter if you like the look
Give them multiple caves even if you aren’t trying to breed. It cuts down on bickering and you’ll see them out in the open more because they feel like they can duck away fast.
Substrate isn’t a big deal. I’ve kept them on sand and on small gravel. What matters more is that your tank isn’t bare. A planted, “cluttered” setup makes them way less shy.
3) What to feed them
Peacock gudgeons are micro-predators. They’ll eat prepared foods, but they’re pickier than, say, tetras. If you want them colored up and acting confident, mix in frozen/live foods.
- Staples that usually work: high-quality micro pellets, small soft granules
- Frozen foods they go nuts for: brine shrimp, daphnia, bloodworms (don’t overdo bloodworms)
- Live treats: baby brine shrimp, grindal worms, mosquito larvae (if you can do it safely)
If they ignore pellets at first, don’t panic. Start with frozen brine shrimp for a week, then “sneak in” pellets during feeding so they learn the routine.
They’re not the fastest at mealtime. In a busy community tank, food can vanish before they even notice it. I like target-feeding with a pipette or dropping food near their favorite cave.
4) Behavior and tankmates
They’re peaceful but a little sassy with each other—lots of posing and short chases, especially males. It’s more “arguing over parking spots” than real violence if you provide space and cover.
- Great tankmates: small rasboras, peaceful tetras, Corydoras, Otocinclus, small rainbowfish (calm ones), shrimp that are too big to be swallowed
- Use caution with: super fast feeders (danios), fin-nippers, big boisterous fish
- Avoid: anything that can fit them in its mouth, or aggressive dwarf cichlids guarding territory
They do best in a small group if the tank is big enough—seeing other gudgeons makes them bolder. If you keep more than a pair, add extra caves so nobody gets cornered.
Sexing is pretty doable once they’re settled: males usually show brighter color and can have a slightly fuller head/forehead look; females often look a bit rounder in the belly, especially when carrying eggs.
5) Breeding tips
Breeding them is one of the fun parts of this species. If you give them caves and feed well, they’ll often do the rest. The male picks a cave (a small tube, a coconut hut, even a film canister-style cave) and tries to convince a female to lay eggs inside.
- Give multiple cave options with small entrances (they like snug spaces)
- Condition with frozen/live foods for a couple weeks
- Keep the water clean and steady; small regular water changes help trigger spawning
- After eggs are laid, the male usually guards and fans them
If you want to raise fry, pull the cave with eggs to a small grow-out tank with gentle aeration. In a community tank, eggs/fry tend to become snacks.
Fry are tiny. First foods that actually work: infusoria/microworms early on, then baby brine shrimp once they’re big enough. If you’ve never raised small fry, don’t beat yourself up—your first batch is often a learning run.
6) Common problems to watch for
Most issues I see with peacock gudgeons come down to two things: they don’t get enough to eat, or they’re stressed in a too-bare/too-busy tank. Once those are fixed, they’re surprisingly forgiving for a “fancy-looking” fish.
- Not eating / getting skinny: usually outcompeted at feeding time or not recognizing dry food yet
- Hiding constantly: tank is too open, lights too bright, or tankmates are pushy
- Fin damage: often from squabbles between males or from nippy tankmates
- Ich/white spot after purchase: common if they were stressed in shipping; quarantine helps a lot
- Eggs fungusing: low flow in the cave or infertile eggs—gentle aeration near the clutch helps
Skip “mystery meds” as a first move. Test your water, watch their feeding, and check for bullying. A lot of gudgeon ‘disease’ is just stress + not enough food.
If you’re buying them, try to pick fish that are already eating at the store. Bright eyes, full bellies, and steady hovering (not clamped fins in a corner) are good signs. A short quarantine pays off with this species.
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