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
- Tankmates
- With caution
- Swim level
- Bottom
- Difficulty
- Medium
- Breeding
- No record
- Rarity
- Very rare
- Family
- Gyrinocheilidae
- Origin
- Native to the Mekong basin across Laos, Thailand, Cambodia and Vietnam, in flowing rivers and streams where it clings to rock and wood.
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.
Common questions
What size tank does a Spotted algae eater need?
A Spotted algae eater needs at least 53 gal (200 L). It spends most of its time in the bottom.
What temperature and pH does a Spotted algae eater need?
A Spotted algae eater is comfortable at 72–82°F (22–28°C) with a pH of 6.0–8.0.
How big does a Spotted algae eater get?
An adult Spotted algae eater reaches about 11 in (28 cm).
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