TankBud

Rosy loach

Petruichthys sp. 'rosy'

Also known as Rosy botia, Dwarf rosy loach, Yunnanilus sp. rosy, Tuberoschistura arakanensis

FreshwaterFish

Rosy loach (Petruichthys sp. 'rosy')

Care at a glance

Temperature
68–79°F
20–26°C
pH
6.5–8.0
Adult size
1.2 in
3 cm
Minimum tank
14 gal
54 L
Temperament
Peaceful
Social behavior
Shoaling
Swim level
Middle
Diet
Carnivore
Difficulty
Easy
Breeding
Hard
Rarity
Common
Family
Nemacheilidae
Origin
Native to shallow, weedy wetlands and slow streams of eastern Myanmar (Shan State) and northern Thailand, among dense marginal vegetation.

Overview

The rosy loach is a tiny, peaceful shoaling loach for the middle of a planted tank. It is easy to keep.

Did you know

Male rosy loaches flush a deeper rose red and display to each other in a good-sized group. That is when the fish looks its best.

Caring for the rosy loach

Keep rosy loaches in a shoal of at least 8 to 10, in a tank of 14 gal (54 L) or more. A mature planted tank with gentle flow and plenty of cover suits them well. They spend much of the day foraging in loose shoals rather than hiding on the bottom like most loaches.

Keep the water at 68 to 79°F (20 to 26°C) and a pH of 6.5 to 8.0. Soft to moderately hard water is fine, as long as it is clean and stable.

The rosy loach is a micropredator. Feed small live and frozen foods such as daphnia, moina, baby brine shrimp and microworm, plus finely crushed dry food.

It is peaceful and tiny, so it pairs well with small rasboras, pygmy corydoras, shrimp and other nano fish. Larger or pushy tank mates will outcompete it at feeding time. Breeding it is hard.

Good to know

The rosy loach belongs to the stone loach family Nemacheilidae, not the botia loaches most hobbyists picture. It is one of the smallest true loaches. It has been shuffled through several genus names, first sold as Yunnanilus sp. 'rosy' and as Tuberoschistura arakanensis before landing in Petruichthys.

In the wild

The rosy loach is native to eastern Myanmar's Shan State and northern Thailand. It lives in shallow, weedy wetlands and slow streams, in warm, still or slow-moving water thick with plants.

Weekly picks

Tank mates

The rosy loach is a peaceful, shoaling species that keeps to the middle. 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 rosy loach need?

A rosy loach needs at least 14 gal (54 L). It spends most of its time in the middle.

What temperature and pH does a rosy loach need?

A rosy loach is comfortable at 68–79°F (20–26°C) with a pH of 6.5–8.0.

What does a rosy loach eat?

A rosy loach is a micropredator that eats small live and frozen foods such as daphnia, moina, baby brine shrimp and microworm. Add finely crushed dry food as well.

How big does a rosy loach get?

An adult rosy loach reaches about 1.2 in (3 cm).

Does a rosy loach need a group?

Yes. A rosy loach is a shoaling species and should be kept in a group, not singly.

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