Peacock Gudgeon Care: The Complete Guide

The peacock gudgeon is one of the most underrated gems in the freshwater hobby. It's small, brilliantly colored, and surprisingly easy to breed — yet most fish stores never stock it. If you've been looking for a show-stopping nano fish that won't bully its tankmates, this is it.

This guide covers everything you need to know: tank setup, feeding, sexing, breeding, and the most common beginner mistakes to avoid.

Species Snapshot

The peacock gudgeon (Tateurndina ocellicauda) is a small freshwater fish native to Papua New Guinea. It lives in slow-moving streams and rivers with dense vegetation and soft, slightly acidic water.

Despite the common name "peacock gudgeon," it's not a true gudgeon. It belongs to the family Eleotridae and is more closely related to sleeper gobies. You'll also hear it called the peacock goby — both names are used interchangeably in the hobby.

Anatomy and Appearance

Few nano fish match the peacock gudgeon for sheer visual impact. The body is elongated and slightly compressed, with large round eyes and a blunt snout. The fins are rounded and flowing, giving the fish a soft, elegant look in the water.

The base color ranges from silver-blue to pale violet. Broken horizontal stripes of red and orange run along the flanks. The most distinctive feature is the bold black eyespot (ocellus) near the base of the tail — this is what gives the species its name ocellicauda, meaning "eyed tail."

The fins show vivid yellow and red banding, especially on males. When a male displays to a rival or a potential mate, his colors intensify dramatically. It's one of the best color shows you'll see in a freshwater nano tank.

Coloration

Peacock gudgeons are sexually dichromatic, meaning males and females look noticeably different. Males are more intensely colored overall, with brighter red and orange patterning and more elaborate fin markings. Females tend to be slightly duller but are still very attractive fish.

Coloration can fade when fish are stressed, newly introduced, or kept in poor conditions. A healthy peacock gudgeon in a well-planted tank will display its full colors constantly.

Sexual Dimorphism

Sexing peacock gudgeons is easier than most small fish. Here's what to look for:

The nuchal hump on males becomes more pronounced with age. A gravid female will develop a noticeably yellow belly — this is one of the clearest signs she's ready to spawn.

Ideal Aquarium Setup

Peacock gudgeons are not hard to keep, but they do best in a tank that mimics their natural habitat. Get this right and you'll have healthy, colorful fish that may even spawn without much encouragement.

Tank Size

A 15-gallon tank is the minimum for a small group. A 20-gallon long gives you more floor space and makes it easier to keep a peaceful community. These fish aren't strong swimmers and prefer slow-moving water, so a longer tank beats a taller one.

Water Parameters

Peacock gudgeons are adaptable to a fairly wide range of water conditions. They thrive in:

• Temperature: 72–79°F (22–26°C)
• pH: 6.0–7.8 (neutral to slightly acidic is ideal)
• Hardness: 5–12 dGH
• Ammonia/Nitrite: 0 ppm (non-negotiable)
• Nitrate: Under 20 ppm

They're more sensitive to ammonia and nitrite spikes than hardier species. Don't rush the nitrogen cycle before adding them.

Filtration and Flow

Use a gentle filter. These fish come from slow-moving streams and don't appreciate a strong current. A sponge filter or a low-flow HOB filter with a spray bar or baffle works perfectly. Sponge filters are especially popular for breeding setups because they also provide surface area for beneficial bacteria without sucking up fry.

Plants and Decor

Heavy planting is highly recommended. Peacock gudgeons feel secure among dense vegetation and will show better colors when they're not stressed. Use a mix of:

• Background plants: Vallisneria, hornwort, or java fern
• Midground plants: Anubias, cryptocorynes
• Floating plants: Frogbit or water sprite (reduces surface light and stress)

Add caves, driftwood, and hiding spots. Coconut shells and aquarium caves are especially useful during breeding. Males will claim and guard a cave, and that's where spawning happens.

A dark substrate helps. These fish come from tannin-stained rivers. Fine dark sand or a black gravel substrate makes their colors pop and helps them feel at home.

Diet and Feeding

Peacock gudgeons are carnivores. In the wild, they eat small invertebrates, insect larvae, and zooplankton. In captivity, they need a protein-rich diet to thrive and show their best colors.

What to Feed

They may ignore dry flake food at first, especially if they were raised on live or frozen foods. Start with frozen bloodworms or brine shrimp, then slowly introduce high-quality micro pellets alongside.

Feeding Tips

Feed small amounts twice a day. These are small fish with small stomachs. Overfeeding is one of the most common mistakes — uneaten food spikes ammonia fast in a smaller tank.

If your peacock gudgeons seem uninterested in food, check water temperature first. Below 72°F, they become sluggish and lose their appetite.

Temperament and Tank Mates

Peacock gudgeons are peaceful community fish. They won't bother most tankmates and aren't particularly territorial outside of breeding season. However, males can be aggressive toward each other, especially in a small tank.

Keep no more than one male per 15 gallons unless the tank is heavily planted and broken up with sight lines. Two males in an open 10-gallon will fight constantly.

Best Tank Mates

Good companions are similarly sized, peaceful fish that won't outcompete peacock gudgeons for food:

• Small rasboras (chili, harlequin, lambchop)
• Ember tetras or neon tetras
• Pygmy corydoras
• Otocinclus
• Small livebearers (endlers, guppies)
• Dwarf shrimp (with caution — gudgeons may eat shrimp fry)

Fish to Avoid

• Large cichlids or any aggressive species
• Fin nippers (tiger barbs, serpae tetras)
• Fish that compete aggressively for the same bottom/mid-water space
• Very fast fish that will steal all the food before gudgeons can eat

Peacock gudgeons tend to be slow, deliberate feeders. Fast, aggressive eaters will out-compete them at feeding time.

Breeding Peacock Gudgeons

This is where peacock gudgeons really shine. They're one of the more accessible breeding projects in the freshwater hobby, even for beginners. With the right setup, a healthy pair will spawn regularly and the male will guard the eggs.

Setting Up a Breeding Tank

A dedicated 10–15 gallon breeding tank gives the best results. Set it up with:

• A sponge filter (won't suck up eggs or fry)
• Dense planting or moss
• At least one spawning cave or tube per male
• Slightly warmer water: 77–79°F
• Soft, slightly acidic water: pH 6.5–7.0

Conditioning the Pair

Before attempting to breed, condition the pair for 1–2 weeks on high-quality live or frozen foods. Frozen bloodworms, live brine shrimp, and daphnia work well. A female in breeding condition will develop a visibly yellow-orange belly.

The Spawning Process

The male will claim a cave and begin displaying to the female — flaring fins, intensifying colors, and swimming in tight circles near the cave entrance. If the female accepts him, she'll enter the cave and deposit eggs on the ceiling or walls.

A typical clutch is 50–100 eggs. After spawning, the female leaves. The male guards the eggs aggressively and fans them with his fins to keep oxygen flowing and prevent fungus. This paternal care is unusual in nano fish and fascinating to watch.

Eggs hatch in 7–10 days depending on temperature. The male continues to guard fry for a few days after hatching. Remove the male once fry are free-swimming to prevent accidental predation.

Raising the Fry

Fry are tiny but not especially delicate. Start feeding with:

• Infusoria or commercial fry food for the first week
• Baby brine shrimp (freshly hatched) from day 7–10 onward
• Micro worms as an alternative

Do small, frequent water changes (10% daily or every other day) to keep water quality pristine. Fry grow relatively quickly and will start showing adult coloration by 6–8 weeks.

Common Mistakes to Avoid

Even experienced hobbyists sometimes stumble with peacock gudgeons. Here are the mistakes that come up most often:

Buying just one fish. Peacock gudgeons are social and do best in groups of 4–6. A single fish will be reclusive and stressed. Buy at least a small group.

Keeping too many males in a small space. Males compete for caves and territory. In an undivided 10-gallon, two males will fight until one is stressed to death. Add plants and caves, or keep a single male with multiple females.

Feeding only dry flake food. These are carnivores. Flake food alone won't keep them healthy long-term. Supplement with frozen bloodworms and brine shrimp at minimum.

Skipping the cave. Without a spawning cave, males have no territory to defend and pairs may never breed. Even if you're not trying to breed them, caves reduce stress and make the fish behave more naturally.

Introducing them to tanks with strong current. Peacock gudgeons come from slow water. A powerful filter or powerhead will exhaust them and suppress their immune system. Always baffle strong flow.

Overcrowding the breeding tank. During spawning, the male becomes territorial. Too many fish in the breeding tank will stress the male and lead to failed spawning attempts.

Are Peacock Gudgeons Hard to Keep?

For most hobbyists with basic aquarium experience, peacock gudgeons are not hard to keep. They tolerate a wide pH range, accept a variety of foods once settled in, and are peaceful with most community fish.

The areas where they require more attention are water quality (they're sensitive to ammonia spikes) and flow rate (they need calmer water than many fish). Get those two things right and they're genuinely easygoing.

For complete beginners, it's worth getting comfortable with the nitrogen cycle and basic water testing before adding peacock gudgeons. Once you're past that learning curve, these fish are a joy to keep.

Where to Buy Peacock Gudgeons

(Estimates only — actual prices on Amazon may vary.) Peacock gudgeons aren't always stocked at big-box pet stores, but they're increasingly available through specialty fish shops and online retailers. Expect to pay $5–$12 per fish depending on source and quality.

When buying, look for:

• Fish that are actively swimming (not hiding at the bottom)
• Vivid, full coloration on males
• No clamped fins or visible lesions
• Fish that respond to food being dropped in

Avoid tanks with sick or dead fish, even if the gudgeons themselves look healthy. Disease spreads fast in a shared system.

Online specialty retailers often have better stock quality than local stores for this species. Shipping stress is real — let new arrivals acclimate slowly and don't feed for 24 hours after introduction.