Fewpored gudgeon

Where they come from

Fewpored gudgeons are an Oxyeleotris from Australia-New Guinea country. Think warm, slow backwaters, side creeks, floodplain pools, and billabongs with leaf litter, roots, and sand-mud bottoms. They spend a lot of time parked on the substrate, watching for bite-size movement.

Setting up their tank

Give them a footprint to roam, not just height. A single adult does well in a 30-40 gallon tank with a 30-inch or longer footprint. A pair or a small group needs more like a 55+. They appreciate dimmer light and lots of cover.

• Substrate: sand or fine smooth gravel. They like to sit and scoot.
• Hardscape: stacked rocks, driftwood, PVC elbows, and tight caves. Multiple hide spots reduce scuffles.
• Plants: optional. Tough plants on wood/rock (Anubias, Java fern) or floaters to break light.
• Flow: gentle. Use a spray bar or baffle. They are not river rockets.
• Lid: tight-fitting with no gaps. They can and will jump.
• Filtration: steady and mature. Aim for low nitrate and spotless ammonia/nitrite.
• Water: 24-28 C (75-82 F), pH 6.5-7.8, GH 2-12 dGH. They handle a range if it is stable and clean.

What to feed them

They are carnivores and prefer meaty foods. Most will take frozen from day one and can be trained to quality sinking pellets with a little persistence.

• Staples: frozen prawn/shrimp pieces, bloodworms, mysis, chopped earthworm, blackworms (rinsed).
• Dry foods: sinking carnivore pellets or soft pellets. Start by mixing with frozen to get them interested.
• Treats: live foods to spark appetite, but do not rely on feeders. Quarantine anything live.

Feed once daily, with one light day or skip day per week. They pack on weight easily. A slightly lean gudgeon is healthier than a stuffed one.

How they behave and who they get along with

Think quiet ambush hunter. They sit, stare, and pounce. Not hyper, not shy once settled. They pick territories around a cave or log.

• Good tankmates: medium, calm fish that use other zones. Rainbowfish (medium species), larger tetras/barbs, peaceful cichlids of similar size, and tougher catfish like bristlenose.
• Questionable: bottom-dwelling gobies/gudgeons of similar shape and size. Expect posturing and nips unless the tank is big with multiple caves.
• Not suitable: nano fish, tiny rasboras, shrimp, or anything bite-sized. Eventually they become snacks.

Breeding tips

They are cave spawners. A conditioned pair will choose a snug cavity, the female sticks eggs on the roof or wall, and the male guards and fans them.

• Sexing: males often show a broader head and may color up a bit more around the head and fins when in the mood. It is subtle.
• Triggers: slightly warmer water (around 27-28 C), heavy feeding on live/frozen, and a recent big water change.
• Spawning site: narrow tubes (1-1.5 inch PVC elbows, bamboo, rock crevices). Entrance should be just wide enough for the male.
• Post-spawn: the male stays on eggs. You can leave him or pull the cave if other fish are nosy.

Hatching is fairly quick, but raising the larvae is the hard part. Reports vary by collection locality. Some batches take newly hatched brine shrimp after yolk absorption; others produce much smaller larvae that need rotifers/infusoria first. Be ready with greenwater and rotifers in case they ignore brine shrimp.

Common problems to watch for

• Jumping during the first week or after spooks. Keep the lid tight and the room calm.
• Overfeeding and fatty liver. Keep portions modest and vary foods.
• Injury from territory fights with lookalike bottom dwellers. Add caves and breaks in sight lines.
• Internal parasites from wild-caught or live foods. Quarantine new fish and deworm if you see stringy white feces or weight loss.
• Bacterial or fungal fuzz on scrapes. Clean water and a little salt can help; medicate if it spreads.
• Stress from bright light and bare tanks. Add shade and cover.