Spotted algae eater

Gyrinocheilus pennocki

Also known as Pennock's algae eater, Laos algae eater, Spotted sucking loach

FreshwaterFish

Care at a glance

Temperature: 72–82°F (22–28°C)
pH: 6.0–8.0
Adult size: 11 in (28 cm)
Minimum tank: 53 gal (200 L)
Temperament: Aggressive
Social behavior: Solitary
Swim level: Bottom
Difficulty: Medium
Breeding: No record
Rarity: Very rare
Origin: Native to the Mekong basin across Laos, Thailand, Cambodia and Vietnam, in flowing rivers and streams where it clings to rock and wood.
Family: Gyrinocheilidae

Overview

This fish needs a tank of 200 litres or more at 22 to 28 C and pH 6.0 to 8.0, and it grows large and aggressive with age. Juveniles graze algae, but adults take sinking pellets, vegetable foods and some frozen fare, and their habit of grazing on the flanks of slow, flat-sided fish makes them poor community mates. Best kept singly and only with fast, sturdy tankmates, not with discus, angelfish or other slow-moving species.

In the wild

A large sucker-mouthed algae eater and the less common cousin of the Chinese algae eater, reaching around 28 cm. Young fish rasp algae and biofilm from surfaces with a specialised sucking mouth, but adults grow big, robust and territorial. It comes from flowing water and wants strong current, good oxygen and a spacious tank with plenty of hard surfaces. Wild adults are a food fish in parts of Cambodia.

Good to know

Its family, Gyrinocheilidae, is unusual in having no true stomach and a modified gill opening that lets it breathe while its mouth is clamped to a rock. This lets it hold onto surfaces in fast water and keep grazing without releasing its grip.

Did you know

Like the Chinese algae eater it becomes more territorial and pushy as it grows, so its usefulness against algae fades as it turns into a large, bossy adult.