The pea puffer (Carinotetraodon travancoricus) is the smallest puffer in the world and the only one most aquarists should start with. It is also sold as the dwarf puffer, Indian dwarf puffer, pygmy puffer or bumblebee puffer — all the same fish, endemic to the rivers and backwaters of Kerala and Karnataka in south-west India. At 1 to 1.4 inches it fits a 10-gallon tank, it needs no salt, and it has more visible personality per cubic inch than anything else in freshwater.
Pea Puffer Care at a Glance
| Parameter | Value |
|---|---|
| Scientific name | Carinotetraodon travancoricus |
| Adult size | 1–1.4 in (2.5–3.5 cm) |
| Lifespan | 4–5 years |
| Minimum tank | 5 gal single; 10 gal for a trio |
| Water type | True freshwater — no salt |
| Temperature | 74–82°F (23–28°C) |
| pH | 7.0–8.0 |
| Hardness | 8–15 dGH |
| Diet | Live and frozen only — snails, blackworms, bloodworms |
| Temperament | Territorial, curious, fin-nipper |
| Difficulty | Intermediate — easy water, demanding food |
Pea Puffer Tank Size and Setup
Five gallons holds one pea puffer. Ten gallons is the practical minimum for a group, and a group means three or more — one male and two females is the classic ratio. Never keep exactly two: the subordinate fish becomes a full-time target with nowhere to go.
- Add 3–5 gallons per extra puffer, and add planting at the same time.
- Plant heavily. Java moss, anubias, crypts, hornwort and floating plants. Line of sight is what triggers pea puffer aggression, so the goal is a tank where no fish can see the whole tank at once.
- Low flow. Pea puffers hover rather than swim and get pushed around by a strong filter. A sponge filter or a baffled internal is ideal.
- Sand or fine gravel, driftwood, leaf litter and caves.
- Lid required. They are small, curious and jump when startled.
Work out your exact volume with the tank size calculator.
Pea Puffer Water Parameters
Pea puffers want ordinary hard tap water: 74–82°F (23–28°C), pH 7.0–8.0, 8–15 dGH. Target 77–79°F. They are scaleless, so ammonia and nitrite must read zero and nitrate should stay under 20 ppm. A 10-gallon pea puffer tank needs 30–50% weekly water changes because the diet is entirely protein.
Check your readings with the water parameter checker.
Pea Puffer Food and Feeding
This is the demanding part. Pea puffers do not eat flake or pellet food. Plan the food supply before you buy the fish.
- Snails — the staple. Small bladder and ramshorn snails, roughly the size of the fish's eye. They are food and tooth maintenance in one. Culture your own in a bucket or spare tank.
- Live blackworms. The single most reliable food for getting a new pea puffer eating.
- Frozen bloodworms, brine shrimp, daphnia, cyclops. Thaw in tank water and offer with tweezers or a pipette.
- Frequency: once or twice a day, only as much as the fish clear in two minutes. A pea puffer with a squared-off, bulging belly has had enough.
More detail on the feeding page and the teeth page.
Male vs Female Pea Puffers
Pea puffers are the only commonly kept puffer that can be reliably sexed by eye, and only once they are mature at around 8 months:
| Feature | Male | Female |
|---|---|---|
| Belly stripe | Dark line running down the centre of the belly | No stripe |
| Eye wrinkles | Iridescent creases radiating behind the eye | Absent |
| Body shape | Slimmer, more streamlined | Rounder, fuller |
| Colour | Brighter yellow, higher contrast | More olive, spots more diffuse |
| Size | Slightly smaller | Slightly larger |
Keep two or three females per male. Males chase females hard during spawning attempts, and a lone female bears all of it.
Pea Puffer Tank Mates
A species-only tank is the safest and most rewarding option. If you want company, the requirements are narrow: fast, short-finned, bottom-oriented or too small to interest the puffer, in a tank of at least 20 gallons.
| Tank mate | Verdict |
|---|---|
| Otocinclus | Best option — peaceful, stays low, ignores the puffer |
| Kuhli loach | Workable in 20 gal+ — nocturnal and hidden |
| Pygmy corydoras | Sometimes works — watch for nipped barbels |
| Ember tetra | Risky — fast enough, but fins get sampled |
| Chili rasbora | Risky — small enough to be seen as food by a large female |
| Betta fish | No — long fins are a guaranteed target |
| Guppy | No — slow and long-finned |
| Cherry shrimp | No — this is food, not a tank mate |
| Mystery snail | No — ornamental snails get eaten alive |
| Goldfish | No — wrong temperature, wrong everything |
All ninety pairings are scored in the pea puffer compatibility hub, or test your own list with the compatibility checker.
Breeding Pea Puffers
Pea puffers are one of the few puffers that breed readily in aquariums, which matters because most stock is still wild-caught from a limited range.
- Condition a group on live blackworms and snails for two to three weeks.
- Provide dense java moss — the male drives the female into it to spawn.
- Eggs are scattered singly in the moss and hatch in about five days at 79°F.
- Remove the adults or move the moss; the parents eat eggs and fry.
- Feed fry infusoria and vinegar eels for the first week, then microworms and baby brine shrimp.
More on the puffer breeding page.
Common Pea Puffer Problems
- Refusing food on arrival. Normal for the first days. Live blackworms almost always break the standoff. See not eating.
- Constant chasing. Too few fish, too little planting, or too many males. Add cover first, then rebalance the sexes.
- Internal parasites. Wild-caught stock frequently arrives with worms. A thin fish with white stringy faeces needs a levamisole or praziquantel course.
- Ich. Treat at half dose and raise the temperature to 82°F — scaleless fish absorb medication fast. See diseases.
Frequently Asked Questions
How big a tank does a pea puffer need?
Five gallons for a single fish and ten gallons for a trio of one male and two females. Add three to five gallons for each additional puffer, and plant heavily, because breaking up line of sight matters as much as volume for keeping the peace.
What do pea puffers eat?
Live and frozen food only: small bladder and ramshorn snails, live blackworms, frozen bloodworms, brine shrimp, daphnia and cyclops. They do not eat flake or pellets, and snails are essential to keep their beak worn down.
How long do pea puffers live?
Four to five years in a well-maintained tank, with three to four years being typical. Clean stable water, a varied live and frozen diet, and enough space and cover to avoid constant territorial stress are what make the difference.
How do you tell a male pea puffer from a female?
Mature males have a dark stripe running down the centre of the belly and iridescent wrinkle lines radiating behind the eye, and they are slimmer and brighter yellow. Females are rounder, more olive, and have no belly stripe. The differences appear around eight months.
Can pea puffers live with other fish?
Only carefully. Otocinclus and kuhli loaches work best in tanks of 20 gallons or more. Pygmy corydoras, ember tetras and chili rasboras are risky. Bettas, guppies, ornamental shrimp and snails are not options at all.
How many pea puffers should I keep together?
One, or three or more. Never exactly two, because the subordinate fish becomes a permanent target. A trio of one male and two females in a heavily planted 10 gallon is the standard setup.
Are pea puffers hard to keep?
Their water requirements are easy: ordinary hard freshwater at 74 to 82F. The difficulty is food, because they need a steady supply of live or frozen items and pest snails. Arrange the food supply before you buy the fish.