Siamese Algae Eater Identification Guide
Recognizing the crisp black stripe running straight to the tail tip that distinguishes this true algae-eating fish.
Read the full Siamese Algae Eater encyclopedia entry →
Key identification features
- Slender, torpedo-shaped body, silvery-gold to tan in color
- A single bold, straight-edged black stripe running from the snout through the eye to the base of the tail, without curving upward
- No barbels at the corners of the mouth
- Small ventral mouth with fine rasping teeth for scraping algae
- Clear or lightly tinted fins without strong black edging
- Typically reaches 5-6 inches (13-16 cm)
Common look-alikes
- Flying fox — very similar stripe but bordered above by a gold line, and has small barbels at the mouth that Siamese algae eaters lack
- False Siamese algae eater (Garra species) — stripe often breaks up or curves near the tail rather than running straight and solid
- Chinese algae eater — stripe is fainter, blotchy, and tends to fade with age rather than staying bold and continuous
Where you'll see one
Native to fast-flowing rivers and streams with rocky substrates in Thailand and the Mekong basin of Southeast Asia. It grazes algae from rocks and wood in well-oxygenated water and is often seen in small loose groups near the bottom.
Frequently asked questions
How do I confirm a true Siamese algae eater versus a flying fox?
Look for mouth barbels and a gold stripe above the black one — flying fox has both, true Siamese algae eaters have neither.
What is the clearest field mark for this species?
A solid black stripe that runs perfectly straight from nose to tail tip without curving or breaking up.
Siamese Algae Eater identified by the community
Recent Siamese Algae Eater catches identified with Fish Identifier.
