Yellowfin Borneo sucker

Gastromyzon viriosus

Also known as Yellowfinned Borneo sucker, Yellow fin hillstream loach

FreshwaterFish

Care at a glance

Temperature: 72–79°F (22–26°C)
pH: 6.5–7.5
Adult size: 2.6 in (6.5 cm)
Minimum tank: 20 gal (75 L)
Temperament: Peaceful
Social behavior: Social
Swim level: Bottom
Difficulty: Difficult
Breeding: No record
Rarity: Rare
Origin: Tatau basin, Sarawak, Malaysia
Family: Gastromyzontidae

Overview

A peaceful Borneo sucker with a colour payoff: the yellow edging on its fins deepens when it is grazing well under good light. Keep a group of five or six over sunlit, algae-covered stone, where it clings and grazes in the current all day. Its diet is mostly biofilm, so mature the tank first, then add fine sinking foods and crushed algae wafers to keep it in condition. Choose small, calm fish that enjoy the same warm, fast, clean water. A tank of around 75 liters with strong flow and a bright, rocky floor suits a group and brings out the fin colour this fish is bought for.

In the wild

Gastromyzon viriosus is known from the Tatau basin in central Sarawak, Malaysian Borneo, living on current-swept stone in warm, clear, fast water. Give it 22 to 26 C, strong flow, and oxygen kept high with vigorous surface movement. Use smooth, algae-covered stones over sand and gravel, and hold pH mildly acidic to neutral at 6.5 to 7.5.

Good to know

A member of the hillstream loach family Gastromyzontidae, Gastromyzon viriosus reaches about 6.5 centimeters. Tan described it in 2006, and the name viriosus means robust or strong, for its thick-set build, though in the trade the fish is known instead for the egg-yolk yellow edging its fins. Its captive breeding has not been reported.

Did you know

Among more than thirty mostly brown relatives, this is the Borneo sucker that turns up wearing bright yellow trim, and it is those fin margins, not the plain body, that sell it.

Tank mates

Yellowfin Borneo sucker is a peaceful, social species that keeps to the bottom. These picks match on water type, temperature, pH, size and temperament.