Amano shrimp (Caridina multidentata) care guide

Group

Shrimp

Other names

Caridina japonica, Yamato numa-ebi, Yamato shrimp, Japanese swamp shrimp, Algae shrimp

Family

Atyidae

Origin

Japan (especially south-west Japan) and Taiwan: coastal streams and rivers

Water

freshwater

Maximum size

5 cm

Temperature

18–27°C

pH

6.5–7.6

Hardness

4–12 dGH, 3–10 dKH

Minimum tank

38 litres

Care level

beginner

Temperament

peaceful

Lifespan

2–3 years

Care

The Amano shrimp is one of the best-known algae eaters in the hobby. It has a translucent grey-green to tan body with a pale stripe down the back and lines of reddish-brown dots or dashes along the sides. Aquarists called it Caridina japonica until a 2006 study showed the correct name is Caridina multidentata. It is named after the aquascaper Takashi Amano, who brought it into the hobby in the early 1980s. Wikipedia gives a typical size of 2.5–3.5 cm; LiveAquaria lists females up to about 5 cm. Keep it in a mature, planted tank of at least 38 litres with hiding places, in groups of three or more. It is hardy and tolerates a broad range: about 18–27 °C and pH 6.5–7.6 suit it well. It comes from fast-flowing coastal streams and copes well with current. LiveAquaria notes it tolerates low to moderate salt levels. It is an accomplished escape artist, so cover the tank. Clean-up role: it eats soft and filamentous algae, leftover food and detritus, and is among the most effective shrimp for algae control when enough are kept (one per 4–8 litres is a common guide). It will not clear established black beard algae on its own. When food is short, feed sinking pellets or flake. Copper: copper-based medicines and some plant fertilisers are toxic to shrimp, snails and most other invertebrates. Never dose them in a tank holding this animal, and check the label of any treatment or fertiliser before use. Like other crustaceans it carries copper-based haemocyanin in its blood and is very sensitive to copper. Sources: LiveAquaria (liveaquaria.com/products/japonica-amano-shrimp); Wikipedia (en.wikipedia.org/wiki/Caridinamultidentata). Checked October 2026.

Diet

Omnivore and keen grazer of algae, biofilm and detritus; it will also take leftover fish food. If algae runs short, feed sinking algae wafers, shrimp pellets, blanched vegetables or good-quality flake. Adults are bold and can grab food from smaller shrimp.

Breeding

Sexing: females are larger and their lower row of side dots is made of longer dashes; males show more evenly spaced dots. Eggs are laid and hatch in fresh water, but the shrimp is amphidromous: the tiny larvae drift down to the sea and develop in salt water before the young return to fresh water. Breeding in captivity is therefore very difficult. Larvae must be moved to full-strength or near-full-strength seawater, fed on phytoplankton for several weeks and then moved gradually back to fresh water. Few hobbyists raise them, and almost all stock is wild-caught or commercially bred.

Compatibility and tank mates

Peaceful. Good with small, peaceful community fish, other shrimp and snails, and safe with plants (it may tear at very soft or dying leaves if starved). Large or predatory fish (cichlids, big barbs, most loaches) will eat it. LiveAquaria also lists pond use with koi that will not eat it, in frost-free conditions only.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.