Rosy loach
Petruichthys sp. 'rosy'
intermediate careOverview
The rosy loach (Petruichthys sp. ‘rosy’, long traded under Tuberoschistura) is a delightful true nano loach from Myanmar — under 3 cm, flushed with warm pink and orange and marked with dark blotches when it is happy. Unlike most loaches it is a busy, sociable shoaler that spends the day dashing about the middle and lower tank. Peaceful, plant-safe and endlessly active, it is one of the finest small loaches for a planted nano.
Tank & water
A shoal thrives in a mature, planted 38-litre (10-gallon) tank or larger.
- Temperature: 22–26 °C from a small heater.
- Water: soft to neutral, pH 6.5–7.5, clean and stable; they dislike the swings of a new tank. Test with a kit.
- Planted with hiding places: fine-leaved plants, wood and leaf litter give cover, but they use the open water too.
- Gentle flow: a soft sponge filter keeps water clean without a strong current.
Feeding
Rosy loaches are small-mouthed micropredators and omnivores. Offer fine crushed micro-pellets, powdered foods and sinking nano foods, supplemented generously with small live and frozen fare — baby brine shrimp, daphnia, cyclops and microworm. Make sure enough reaches the bottom, as they are tiny and easily out-competed.
Behaviour & tankmates
Completely peaceful and shrimp-safe once shrimp are adult, the rosy loach is a superb community nano. Good tankmates include chili rasboras, celestial pearl danios, small tetras and cherry shrimp. Avoid anything large, fast or nippy. They appreciate a mature tank with some biofilm and gentle current.
A mature tank also supplies the biofilm and micro-life they graze between feedings, which helps keep a group in condition. Because they occupy the lower and middle water, they combine well with surface-oriented nano fish to make lively use of the whole tank.
Give the rosy loach a good-sized shoal, a mature planted tank and small foods, and you get one of the most engaging, low-fuss nano loaches in the hobby — see our best nano aquarium picks and how to set up a nano tank.
Rosy loach — frequently asked questions
How many rosy loaches should I keep?
Keep at least eight to ten, and ideally more. The rosy loach is a genuinely social shoaling loach, not a solitary bottom-dweller — in a proper group they are constantly active and colour up nicely, whereas in ones and twos they hide, pale and behave nervously.
Are rosy loaches a good nano fish?
Yes, they are one of the best true nano loaches. At under 3 cm and completely peaceful, a shoal fits a modest planted tank, they don't dig up plants, and they mix well with other small, gentle nano fish and shrimp. Their small mouths do mean they need appropriately small foods.
What water do rosy loaches need?
Soft to neutral, warm, stable water around pH 6.5–7.5 and 22–26 °C, in a mature, well-planted tank. Like most tiny fish they are sensitive to swings and to an uncycled tank, so add them only once the aquarium is established and clean.
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