Siamese algae eaters with shrimp

By the Shrimp Tank Hub editorsUpdated Oct 26, 2026Research-based

The Siamese algae eater, or SAE (Crossocheilus oblongus, sometimes C. langei), is a slender Southeast Asian river fish with a black stripe from snout to tail, famous for eating hair algae and even black beard algae (The Shrimp Farm, Aquarium Co-Op). It is a popular answer to "what eats algae?", so people often ask whether it belongs in a shrimp tank. The honest answer depends on your shrimp and your tank size.

Siamese algae eaters at a glance

Will a Siamese algae eater eat shrimp?

• Dwarf shrimp: the references disagree. The Shrimp Farm's SAE care guide says to avoid small shrimp like Neocaridina, and Aquarium Co-Op says SAEs will eat dwarf shrimp. The Shrimp Farm's general tankmates list rates the SAE "does not eat adult shrimp" and says it gets along with shrimp in a well-planted tank. Two of three statements point the same way, so we treat cherry shrimp with an SAE as a risk, not a safe pairing.
• Shrimplets: a 6-inch, always-hungry forager will find babies. Aquarium Co-Op describes juveniles foraging nonstop for leftovers.
• Larger shrimp: Aquarium Co-Op says SAEs seem to leave most snails and larger shrimp alone, and The Shrimp Farm says Amano shrimp should be fine, along with Atyopsis fan shrimp, which also like strong flow.

Our reading: if you already have an SAE in a large community tank, Amano shrimp are the shrimp to add. If you have a dwarf shrimp tank with an algae problem, an SAE is the wrong tool: it needs far more space than a typical shrimp tank and may eat the shrimp. See cherry shrimp tank mates for fish that suit small shrimp tanks.

Not a nano fish

The Shrimp Farm says SAEs are not suitable for small aquariums and need a tank of 55 gallons (long) or more for a small group, because of their size and activity level. Aquarium Co-Op says a single SAE can live in 50 to 55 gallons. Seriously Fish wants a 60 × 18 in base for a group and says the species needs spotless, well-oxygenated water with good water movement. Many shrimp tanks are much smaller than that, so in practice an SAE only fits a large community tank.

Matching the water

The shared zone is our comparison of the published ranges, not a tested target. Water chemistry is not the problem with this pairing; size and appetite are. The Shrimp Farm says SAEs should only go into fully cycled, mature tanks with weekly water changes. See shrimp tank temperature and shrimp tank pH.

Do SAEs really eat algae?

Yes, with limits. The Shrimp Farm says SAEs can help keep hair algae under control and some will nibble black beard algae, which few other fish touch, but that no fish replaces regular maintenance. Aquarium Co-Op says juveniles eat hair and black beard algae, and that SAEs prefer fish food over algae when given the choice. The Shrimp Farm says a home aquarium is usually too clean to feed a group on algae alone, and recommends herbivore foods, algae tabs, spirulina and blanched greens rather than protein-rich foods. For shrimp-safe ways to deal with algae, see algae in a shrimp tank.

Make sure it is a true SAE

• Chinese algae eater (Gyrinocheilus aymonieri): has a sucker mouth (The Shrimp Farm), can reach 11 inches (Aquarium Co-Op), and The Shrimp Farm's tankmates list calls it more aggressive than the SAE.
• Flying fox (Epalzeorhynchos kalopterus): yellowish or gold stripe and black-marked fins (The Shrimp Farm, Aquarium Co-Op).
• False Siamese algae eater (Garra cambodgiensis): looks very similar but has a yellow body stripe (The Shrimp Farm).
• True SAE: a single black stripe from snout to tail with clear fins (Aquarium Co-Op).

Safer algae helpers for a shrimp tank

• Amano shrimp graze soft and hair algae and live peacefully with dwarf shrimp; see Amano shrimp care.
• Nerite snails graze film and spot algae; see nerite and mystery snails with shrimp.
• Otocinclus are small, shrimp-safe grazers for a mature tank; see otocinclus with shrimp.
• Bristlenose plecos suit larger tanks; see bristlenose plecos with shrimp.

If you keep both anyway

• Use a large, mature, heavily planted tank with lots of moss so shrimplets can hide.
• Start with a well-established, prolific colony, or choose Amano shrimp.
• Feed the SAE properly so it is not foraging hungry.
• Quarantine the fish separately. Practical Fishkeeping says many fish medications are not safe for invertebrates. If fish get sick, ask a fish veterinarian or an experienced store about treatment that won't harm the shrimp. See how to quarantine and is copper toxic to shrimp.

Common mistakes

• Buying an SAE for a 10- or 20-gallon shrimp tank.
• Buying a Chinese algae eater or flying fox by mistake.
• Expecting an SAE to live on algae alone.
• No lid; Aquarium Co-Op says they jump.

Track it

Log temperature, pH, GH and TDS on the free Water Parameter Log printable so you can keep the tank in the range both species share.

Frequently asked questions

Will a Siamese algae eater eat cherry shrimp?

It might. The Shrimp Farm's SAE care guide says to avoid small shrimp like Neocaridina, and Aquarium Co-Op says SAEs will eat dwarf shrimp. The Shrimp Farm's tankmates list is more relaxed, so the references disagree.

Can Siamese algae eaters live with Amano shrimp?

Usually. The Shrimp Farm says Amanos should be fine, and Aquarium Co-Op says SAEs seem to leave most larger shrimp alone.

Can I put a Siamese algae eater in a 10 or 20 gallon shrimp tank?

No. SAEs grow to about 6 inches; The Shrimp Farm says 55 gallons or more for a small group, and Aquarium Co-Op says 50 to 55 gallons for one.

Do Siamese algae eaters eat black beard algae?

Some do. The Shrimp Farm says some SAEs nibble black beard algae, and Aquarium Co-Op says juveniles eat it, but SAEs prefer fish food when they can get it.

What is a safer algae eater for a shrimp tank?

Amano shrimp, nerite snails and, in a mature tank, otocinclus are the usual shrimp-safe choices.

How do I tell a Siamese algae eater from a Chinese algae eater?

The Chinese algae eater has a sucker mouth and grows much larger. A true SAE has one black stripe from snout to tail and clear fins.

Sources: The Shrimp Farm, Shrimp tankmates and compatibility (Siamese algae eater Crossocheilus oblongus, can also be C. langei, up to 6 in, 55+ gallons, easy, does not eat adult shrimp; gets along with shrimp in a well-planted tank; not a nano fish; not the more aggressive Chinese algae eater); The Shrimp Farm, True Siamese algae eater care (up to 6 in; lookalikes Gyrinocheilus aymonieri with sucker mouth, Epalzeorhynchos kalopterus and Garra cambodgiensis with yellowish stripes; fast-flowing streams in Southeast Asia; not for small aquariums, 55 gallons long or more for a small group; fully cycled, mature tanks, weekly water changes; group of at least five; peaceful but active; avoid small shrimp like Neocaridina, Amanos should be fine, Atyopsis fan shrimp; helps with hair algae, some nibble black beard algae, not a replacement for maintenance; supplement with herbivore foods, avoid protein-rich foods); Aquarium Co-Op, Care guide for Siamese algae eaters (6 in/15 cm; Chinese algae eater up to 11 in with suckermouth; flying fox with gold line and black-marked fins; single SAE in 50–55 gallons with tight lid; 68–80 °F, pH 6.0–8.0, soft to hard water; can be semi-aggressive to its own kind, one alone or three or more; will eat dwarf shrimp but seem to leave most snails and larger shrimp alone; juveniles eat hair and black beard algae; prefer fish food over algae); Seriously Fish, Crossocheilus langei (Siamese algae eater) (150 mm SL; 60 × 18 in base, about 80 gallons, for a group; flowing-stream set-up, spotless, well-oxygenated water; 68–79 °F, pH 6.0–7.5, 1–15 dGH; peaceful; group of six or more); Practical Fishkeeping, What can I keep with shrimp? (many fish medications unsafe for invertebrates); The Shrimp Farm, Red rili shrimp tank set-up and care (cherry-type Neocaridina: 65–85 °F, pH 6.2–8.0, GH 4–8). The shared water zone is our own comparison of these ranges.