I’ll never forget the first time I introduced a pea puffer into a community tank. I had done my research, carefully picked tank mates, and felt pretty confident, until I watched that tiny, golf-ball-sized fish stalk a neon tetra like a miniature aquatic velociraptor.

Within minutes, it was clear: this little puffer had no interest in making friends.

Pea puffers (Carinotetraodon travancoricus) are some of the most fascinating fish in the hobby, small, intelligent, and brimming with personality. But they come with a reputation: curious yet territorial, bold yet aggressive. Many aquarists assume they must live alone, but with the right approach, a carefully selected community setup is possible.

In this blogpost, I’ll walk you through how to pick the right tank mates, manage aggression, and create an environment where your pea puffer won’t turn into an underwater menace, because trust me, I’ve learned the hard way.

Understanding pea puffer behavior

If you’ve ever kept a pea puffer, you know they don’t just swim, they prowl. Unlike your typical community fish, these tiny predators are always on the lookout, sizing up their surroundings with beady, intelligent eyes. Their territorial and aggressive nature isn’t just for show, it’s instinctual. In the wild, they hunt small invertebrates, with a particular obsession for snails, which they crush with their sharp beaks.

Don’t let their size fool you. At barely an inch long, a single pea puffer needs at least 5 gallons of space, more if you’re considering multiple. Cramped conditions lead to heightened aggression, and without careful planning, tank mates can quickly become targets. Fin-nipping is common, especially with slow-moving fish.

This is why choosing the right companions is crucial. To avoid stress and injury, any potential tank mate must be fast, non-aggressive, and able to handle the puffer’s feisty personality, or risk becoming a casualty of curiosity.

Ideal pea puffer tank mates

Tank mate	Compatibility	Reason for Compatibility	Recommended tank size (gallons)
Otocinclus Catfish	High	Peaceful bottom dweller, avoids conflict	20+
Kuhli Loach	High	Nocturnal, hides during the day	20+
Pygmy Corydoras	Moderate	Fast-moving, non-threatening	20+
Neon Tetra	Moderate	Fast swimmer, can evade aggression	20+
Ember Tetra	High	Small, active, avoids fin-nipping	20+
Harlequin Rasbora	High	Non-aggressive, hardy schooling fish	20+
Amano Shrimp	Moderate	Large shrimp, fast enough to escape puffer	20+
Glowlight Tetra	Moderate	Similar to neon tetras, avoids conflict	20+
Betta Fish	Low	Territorial, fights with puffers	N/A
Guppies	Low	Slow, colorful, prone to fin-nipping	N/A
Angelfish	Low	Can be aggressive, stresses puffers	N/A
Gouramis	Low	Can be territorial, may provoke aggression	N/A
Large Cichlids	Very Low	Predatory, may eat pea puffers	N/A
Cherry Shrimp	Very Low	Small and vulnerable, likely to be eaten	N/A

Finding the perfect tank mates for a pea puffer is like picking roommates for a grumpy genius, it’s all about compatibility.

The key? Similar water parameters (pH 6.5–7.5, temp 74–82°F), a peaceful temperament, and the ability to evade occasional aggression. Anything slow-moving or flashy? Bad idea. Anything too aggressive? Even worse.

Here’re the best tank mates for your pea puffer:

Otocinclus catfish

These peaceful, algae-eating bottom dwellers keep to themselves, making them perfect companions. Their speed and armor-like bodies help them avoid trouble.

Kuhli loach

A nocturnal ninja. Kuhlis spend most of their time burrowed or hiding, avoiding conflict altogether.

Pygmy corydoras

Small, schooling, and constantly on the move, too quick for a pea puffer to bother.

Neon Tetras & Ember Tetras

Their speed and schooling behavior help them evade nips. Plus, they share similar water preferences.

Harlequin Rasboras

Hardy, non-aggressive, and active enough to steer clear of puffers.

Amano Shrimp

While some shrimp get eaten, Amanos are larger and fast enough to dart away from trouble.

Glowlight Tetras

Similar to neons, they move fast and won’t provoke the puffer.

With the right balance of tank mates, a carefully planned setup, and close observation, you can create a surprisingly harmonious pea puffer community, without turning your tank into an underwater battleground.

Tank mates to avoid

Not every fish (or invertebrate) can handle a pea puffer’s attitude. Some are too slow, too flashy, or simply too aggressive, creating a recipe for disaster. If you value your tank’s peace, avoid these species at all costs:

Betta fish

Think of two hot-headed gladiators trapped in a small arena. Both are territorial, both get easily agitated, and neither backs down. This match-up almost always ends in shredded fins and stress.

Guppies

Their long, flowing tails might as well have a “bite me” sign for a puffer. Slow-moving and colorful, guppies are prime targets for fin-nipping.

Angelfish & Gouramis

Though larger, these species can be just as territorial as a puffer. Expect constant tension and possible fights.

Large cichlids

If it fits in their mouth, they’ll eat it. That includes your tiny pea puffer.

Fancy Shrimp (ex., Cherry Shrimp)

If you’re attached to your shrimp colony, don’t test it. Pea puffers see small shrimp as a tasty snack.

Picking the wrong tank mates can lead to stress, injuries, or worse, so when in doubt, keep your puffer’s territorial instincts in mind.

Setting up the perfect community tank

A successful pea puffer community tank isn’t just about picking the right fish, it’s about designing an environment where everyone thrives.

Start with water parameters that suit both your puffer and its tank mates: pH 6.5–7.5, temperature 74–82°F, and soft to moderately hard water. Stability is key, so invest in a reliable heater and filter.

Aquascaping matters

Pea puffers don’t just appreciate plants, they need them. Java Moss, Anubias, and Hornwort create natural barriers, reducing aggression and giving tank mates places to escape unwanted attention. The more hiding spots, the better.

Tank size is crucial

While a single pea puffer needs 5 gallons, a community setup should start at 20 gallons. Overcrowding increases stress and fights, so provide ample swimming space.

Feeding can be tricky

Pea puffers have a voracious appetite for live and frozen foods, but their tank mates may struggle to compete. A targeted feeding strategy, dropping sinking pellets for bottom dwellers and offering frozen bloodworms to puffers, keeps everyone well-fed.

Lastly, environmental enrichment reduces stress. Vary the layout, introduce driftwood, caves, and dense vegetation, and keep an eye on behavior. A happy puffer is a less aggressive puffer, meaning a peaceful, thriving tank for all.

Pea Puffer Tank Mates: A Challenge Worth Taking

Pea puffers may be small, but their personalities are anything but. Their semi-aggressive nature makes tank mate selection a challenge, but with careful planning, the right environment, and close observation, a community setup is possible.

The key? Monitor behavior. Even with the best planning, some puffers simply won’t tolerate company. Always have a backup plan, like a separate tank, if things don’t work out. No fishkeeper likes to admit defeat, but sometimes, a solitary life is what a puffer truly needs.

Have you had success keeping pea puffers with tank mates? Share your experience in the comments!

Happy fishkeeping!