Siamese Algae Eater
Crossocheilus oblongus
Siamese Algae Eater (Crossocheilus oblongus) — Varies care, Peaceful, under Other. Minimum tank in the app: 37 US gal min; aim for 68–79°F and pH 6.5–7.5. The Siamese Algae Eater is an adaptable mid-water swimmer suited for larger aquariums with a balanced mix of plants and open spaces.

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.
Natural distribution
Asia
- East & Southeast Asia
Regional colours match the stocking calculator’s origin map.
Siamese Algae Eater Tank Setup
Create a balanced environment with both open swimming areas and dense plant cover to encourage natural behaviors. Aim for moderate water flow to mimic their native habitats, and use a soft substrate to prevent injury while providing ample hiding spots to reduce stress and territoriality.
What Do Siamese Algae Eaters Eat?
They are opportunistic feeders and may compete for food, especially in a diverse tank. Offer a varied diet, including algae wafers and vegetables, to ensure proper health and vibrant coloration, as a lack of dietary variety may lead to malnutrition.
Siamese Algae Eater Tank Mates
Ideal companions include similarly sized and non-aggressive fish, such as tetras or danios. Larger, more territorial species may provoke aggression, while keeping multiple Siamese Algae Eaters can lead to minor skirmishes; hence, observe their interactions closely when introducing new tank mates.
Are Siamese Algae Eaters Good for Beginners?
Care demand varies with setup and individual fish; use the numbers above as your baseline. Aquarists often underestimate their size and aggression potential, resulting in overcrowding or incompatible tank mates. neglecting to provide sufficient hiding spots can lead to stress and dominance issues, ultimately compromising the health of all inhabitants.
Guides that pair with this fish
- Siamese algae eater guide — ID, diet, and algae expectations.
- Best algae eaters compared — Team solutions beyond one fish.
- Hair algae in aquariums — When biocontrol helps and when it cannot.
Building a community? Run the full list through the stocking calculator before you add anything else.
Log tests and reminders in App-aquatic—free, same data you see here.




