Siamese Algae Eater

Looks how to spot one

Slim scaled minnow

A long, slender, greyish-gold fish with a single dark stripe running from the snout through to the end of the tail fin. The eye is reddish-gold above and pale below, and it has two pairs of small barbels. The stripe can fade quickly so the fish blends with its surroundings.13

Personality what they are like

Peaceful and community friendly. It is a shoaling fish that grows more confident in a group, where members sort out a friendly ranking among themselves.1

Daily activity how busy a day looks

Lively and constantly on the move, browsing surfaces and darting around. It enjoys strong water movement in a river-style tank.1

Grooming and care the hands-on bits

Likes very clean, well-oxygenated water with good flow and regular water changes. Water: about 20-26 C, pH 6.0-7.5, hardness about 1-15 dGH.1

Home where they are happiest

For a group, a tank of at least about 150 x 45 cm base (around 300 litres) with rocks, driftwood, hardy plants and plenty of current.1

Food basics what goes in the bowl

Mainly a plant-based grazer. Feed good vegetable-based dried foods with spirulina, plus blanched vegetables such as peas, courgette and spinach, and occasional fruit; keep rich high-protein foods to a minimum.12

Company who they like around

Keep in groups of six or more.1

The story where it all began

Pieter Bleeker described Crossocheilus langei in 1860. Over the years several look-alike species have been sold under the same common name, which has caused plenty of naming confusion in the hobby. It became popular because it will tackle hard-to-shift algae in planted tanks.231

Recognised by the official bits

IUCN Red List

Data Deficient (assessed 2018).2

Naming note

Fish sold as Siamese algae eater are usually C. langei; the names C. siamensis and C. oblongus are often misapplied in the trade.1