Siamese algae eater
Crossocheilus oblongus
FreshwaterFish
Care at a glance
- Temperature
- 68–79°F
- 20–26°C
- pH
- 6.0–7.5
- Adult size
- 6.3 in
- 16 cm
- Minimum tank
- 37 gal
- 140 L
- Temperament
- Peaceful
- Social behavior
- Shoaling
- Swim level
- Bottom
- Diet
- Omnivore
- Difficulty
- Medium
- Breeding
- No record
- Rarity
- Common
- Family
- Cyprinidae
- Origin
- Thailand, Malaysia
Overview
The Siamese algae eater is a peaceful, shoaling cyprinid for the bottom of a community tank. It is moderately easy to keep.
Did you know
Young Siamese algae eaters are one of the few fish that will actually eat black beard algae, which makes them popular with planted-tank keepers. As they grow, their appetite for it fades, and they switch to easier prepared foods.
Caring for the Siamese algae eater
Keep Siamese algae eaters in a small group of five or more, in a tank of at least 37 gal (140 L). They grow larger than people expect, so plan the tank for their adult size. Smooth surfaces and driftwood give them places to graze.
Keep the water clean, soft and a little acidic, with good, steady flow. Hold it at 68 to 79°F (20 to 26°C) and a pH of 6.0 to 7.5.
They eat algae, but you must supplement it with sinking pellets, wafers and frozen food. Siamese algae eaters are peaceful and active, safe with community tank mates, and they spend the day grazing surfaces. They are widely sold but have no reliable record of breeding in home aquariums.
Good to know
Crossocheilus oblongus is a cyprinid, related to barbs and danios. Its clean black stripe runs into the tail and helps tell it apart from similar look-alikes.
In the wild
Siamese algae eaters come from fast, clear streams and flooded forests in Thailand and Malaysia. The water there is soft, slightly acidic and well oxygenated, over rocks and leaf litter.
Weekly picks
Tank mates
The Siamese algae eater is a peaceful, shoaling species that keeps to the bottom. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.
Guppy
Poecilia reticulata
FreshwaterBrackish2.4 in (6 cm) · 10 gal (38 L)64–82°F (18–28°C)
Yoyo loach
Botia almorhae
Freshwater6.3 in (16 cm) · 42 gal (160 L)66–81°F (19–27°C)
Blue acara
Andinoacara pulcher
Freshwater5.9 in (15 cm) · 42 gal (160 L)72–82°F (22–28°C)
Everett's barb
Barbodes everetti
Freshwater4.7 in (12 cm) · 40 gal (150 L)64–82°F (18–28°C)
Forest halfbeak
Hemirhamphodon pogonognathus
Freshwater3.5 in (9 cm) · 34 gal (130 L)75–82°F (24–28°C)
Emerald catfish
Brochis splendens
Freshwater3.1 in (8 cm) · 40 gal (150 L)70–82°F (21–28°C)
Common questions
What size tank does a Siamese algae eater need?
A Siamese algae eater needs at least 37 gal (140 L). It spends most of its time in the bottom.
What temperature and pH does a Siamese algae eater need?
A Siamese algae eater is comfortable at 68–79°F (20–26°C) with a pH of 6.0–7.5.
What does a Siamese algae eater eat?
A Siamese algae eater grazes algae, but it needs sinking pellets, wafers and frozen food as well.
How big does a Siamese algae eater get?
An adult Siamese algae eater reaches about 6.3 in (16 cm).
Does a Siamese algae eater need a group?
Yes. A Siamese algae eater is a shoaling species and should be kept in a group, not singly.
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