TankBud

Butterfly moth catfish

Erethistes pusillus

Also known as Pusillus moth cat

FreshwaterFish

Butterfly moth catfish (Erethistes pusillus)
The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature
68–79°F
20–26°C
pH
6.0–7.5
Adult size
2 in
5 cm
Minimum tank
14 gal
54 L
Temperament
Peaceful
Social behavior
Social
Swim level
Bottom
Difficulty
Medium
Breeding
No record
Rarity
Rare
Family
Erethistidae
Origin
Brahmaputra and Meghna basins

Overview

The butterfly moth catfish is a cryptic, night-active bottom dweller that disappears into litter and wood by day. It suits a keeper with some experience.

Did you know

The butterfly moth catfish's species name undersells it. Pusillus is Latin for very small or slight, yet it is one of the larger moth cats in the aquarium trade.

Caring for the butterfly moth catfish

Provide a few butterfly moth catfish with a mature tank of at least 14 gal (54 L). Use a soft sand bottom with driftwood, smooth rocks and botanicals for cover and shaded hiding places. Subdued light and a clean, steady flow suit them.

Hold the water at 68 to 79°F (20 to 26°C), soft to medium and close to neutral at pH 6.0 to 7.5. It hunts small invertebrates at night. Offer fine sinking foods in the evening, such as frozen bloodworm, daphnia, baby brine shrimp and sinking pellets. New fish can be slow and picky when settling in, so be patient while they learn to feed.

The butterfly moth catfish is peaceful but shy, so keep a few together. Pair them with small, gentle fish rather than boisterous or large ones, or use a species tank. Breeding is not recorded in aquariums.

Good to know

Erethistes pusillus is a moth catfish in the family Erethistidae. It has serrated pectoral spines that it can spread and lock like a pair of wings. Like its relatives, it wears rough, tuberculed skin. It is also sold as the pusillus moth cat.

In the wild

The butterfly moth catfish lives in gently flowing, well-oxygenated waters of the Brahmaputra and Meghna basins, in northeast India and Bangladesh. It holds among sand, litter and submerged wood.

Weekly picks

Tank mates

The butterfly moth catfish is a peaceful, social species that keeps to the bottom. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a butterfly moth catfish need?

A butterfly moth catfish needs at least 14 gal (54 L). It spends most of its time in the bottom.

What temperature and pH does a butterfly moth catfish need?

A butterfly moth catfish is comfortable at 68–79°F (20–26°C) with a pH of 6.0–7.5.

What does a butterfly moth catfish eat?

A butterfly moth catfish hunts small invertebrates at night. Offer it fine sinking foods in the evening, such as frozen bloodworm, daphnia, baby brine shrimp and sinking pellets.

How big does a butterfly moth catfish get?

An adult butterfly moth catfish reaches about 2 in (5 cm).

Related species