Amano shrimp care: tank size, water, food, tankmates and lifespan
Amano shrimp (Caridina multidentata) are the shrimp many aquarists buy first, usually for algae. They are larger than cherry shrimp, hardy once settled, peaceful with almost everything, and tireless grazers. They also have one big difference from the dwarf shrimp most of this site covers: their larvae need salt water, so a freshwater tank will not grow a colony. This guide covers the tank, water, food, tankmates, molting, lifespan and sexing, plus what to expect if you see a berried female. We haven't run our own trials, so the ranges here are commonly cited figures from hobby references, published research on the species and owner reports.
Amano shrimp at a glance
| Trait | Commonly cited |
|---|---|
| Scientific name | Caridina multidentata (formerly sold as C. japonica) |
| Adult size | Roughly 1.5–2 in (about 3.5–5 cm); females usually larger |
| Temperature | About 64–82 °F (18–28 °C); low to mid 70s °F is a common target |
| pH | About 6.5–7.5 |
| Lifespan | Often 2–3 years, with many reports of longer in stable tanks |
| Temperament | Peaceful; bold eaters that will grab food from smaller shrimp |
| Breeding in freshwater | Eggs hatch, but larvae need brackish to salt water to survive |
Tank size and setup
- Size. Amanos are bigger and more active than Neocaridina, and they are usually kept in groups, so about 10 gallons or more is a common recommendation. A few can live in a smaller planted tank, but stability is harder to hold in small volumes. Our stocking guide covers how bioload adds up if you are mixing them with cherries.
- Cycled and mature. Add Amanos only to a fully cycled tank, ideally one that has been running for a while and has some algae and biofilm. See how to cycle a shrimp tank.
- Plants and cover. They are most comfortable with plants, wood and rock to climb and hide in, especially right after a molt.
- Filtration and oxygen. In the wild they live in flowing streams, and they appreciate clean, well-oxygenated water. A sponge filter or a filter with a sponge-covered intake works well; see our shrimp-safe filter guide. An air-driven sponge filter adds surface movement too.
- A lid. Amano shrimp are known climbers and escapers, particularly in a new tank or when water quality slips. A tight-fitting lid and covered gaps around filters and cables prevent dried-shrimp surprises.
Water parameters
Amanos tolerate a fairly wide range, which is part of why they are popular. Commonly cited targets are a temperature of about 64–82 °F (18–28 °C) and a pH of roughly 6.5–7.5, with zero ammonia and nitrite and low nitrate. Most dechlorinated tap water in the moderate range suits them; see can shrimp live in tap water? Warmer water makes them more active, but some sources note it may also shorten lifespan, so there is no need to run the tank hot. A small adjustable heater helps hold a steady temperature in a cool room; our nano heater guide compares options.
As with all shrimp, the bigger danger is change, not a particular number. Test regularly with a reliable kit (our water test kit guide covers the options), make water changes modest and temperature-matched, and avoid anything containing copper, which is toxic to shrimp. Check medications and plant fertilizers before dosing; our shrimp-safe fertilizer guide explains what to look for.
Adding Amano shrimp to your tank
Amanos are often shipped in groups and can be stressed on arrival. Acclimate them slowly to your water rather than tipping them straight in; a drip over about one to two hours is a common approach. Keep the lid on during and after, because newly added Amanos are the ones most likely to try to climb out. Our drip acclimation guide walks through it step by step.
What Amano shrimp eat (and do they really eat algae?)
Yes, within limits. Amanos are strong grazers of soft algae, biofilm and leftover food, and owners commonly report them clearing hair and thread-type algae from plants and hardscape. They are much less effective on tough algae such as black beard algae or hard green spot algae on glass, so treat them as a clean-up crew, not a cure for an algae outbreak caused by too much light or nutrients.
- Supplement their diet. In a tidy tank, a group of Amanos can run out of algae quickly. Offer a shrimp pellet, algae wafer or blanched vegetable a few times a week, and keep some leaf litter in the tank. Our best shrimp food guide compares common options.
- Feed lightly. Give what the tank clears in a few hours and remove leftovers.
- Expect enthusiasm. Amanos often grab a whole pellet and carry it off. In a mixed tank, scatter food in a few places so smaller shrimp get a share.
Tankmates
Amano shrimp are peaceful and get along with most small, community fish and other shrimp. Their larger size means they are less likely than cherry shrimp to be eaten by small fish, but any fish big enough to fit one in its mouth is still a risk, especially just after a molt.
- Usually fine: small, peaceful fish such as many rasboras, small tetras, otocinclus and small corydoras; snails; cherry and other Neocaridina shrimp.
- Use caution: larger or boisterous fish, and fish that pick at invertebrates. Watch closely if you add any.
- Usually avoid: large cichlids, goldfish and other fish big enough to eat a shrimp.
Amanos and cherry shrimp are a popular pairing. They do not interbreed, and the Amanos stay out of the way of a cherry colony, though they will out-compete baby cherries for food if feeding is very sparse.
Molting
Like all shrimp, Amanos grow by shedding their shell. A clean, empty shell on the substrate is a good sign, not a death. Leave it in for a day or two; the shrimp often eat it. A shrimp that hides for a day or so after molting is normal while its new shell hardens. Failed molts are usually linked to sudden water changes or unstable minerals; our shrimp dying after molting guide covers the causes.
How long do Amano shrimp live?
A lifespan of about two to three years is commonly cited, and many keepers report Amanos living well beyond that in stable tanks. Losses in the first few weeks are more often linked to shipping stress, acclimation or water swings than to age, which is why a slow introduction and a mature tank matter.
Males vs. females
Females are generally larger and have a broader underside where eggs are carried. The most cited visual clue is the dotted line along each side: in females, the lower row is made of longer dashes, while in males it is made of evenly spaced, rounder dots. A mature female may also show a greenish saddle of developing eggs behind the head.
Why Amano shrimp rarely breed in a home aquarium
Amano shrimp do mate in freshwater, and females often carry eggs (become "berried"). The eggs hatch into tiny free-swimming larvae, but in the wild those larvae drift downstream to the sea and develop in salt water before the young shrimp return to fresh water. In a freshwater tank, the larvae do not survive.
Published lab work on Caridina multidentata found larvae surviving to the juvenile stage across a range of brackish to full-strength seawater salinities, and only with suitable cultured foods. In practice this means a separate larval tank, salt mixing, live phytoplankton or similar foods, and a slow move back to fresh water. A few dedicated hobbyists do it, but for most keepers a berried Amano is simply a sign of a healthy, settled shrimp. If you want shrimp that breed on their own, cherry shrimp are the easy choice; see how to breed cherry shrimp.
An Amano shrimp setup checklist
- Cycle the tank, about 10 gallons or more, and let it mature.
- Add plants, wood or rock, and a sponge filter or covered intake.
- Fit a tight lid and cover gaps around equipment.
- Test the water: roughly 64–82 °F, pH about 6.5–7.5, zero ammonia and nitrite.
- Drip-acclimate new shrimp over an hour or two.
- Feed a little extra a few times a week, keep water changes small and regular, and keep copper out.
Our printable water log and maintenance checklist make it easy to keep track of tests and water changes.
FAQ
How many Amano shrimp should I get?
Many keepers start with a small group, often three to six in a 10-gallon tank, and adjust from there. Because they will not breed in freshwater, the number stays the same unless you add more.
Do Amano shrimp eat algae?
Yes. They graze soft algae, biofilm and leftovers and are especially known for hair and thread algae. They do little against tough algae like black beard or green spot, and they still need some extra food in a clean tank.
Can Amano shrimp live with cherry shrimp?
Yes, it is a popular pairing. They do not interbreed. Feed in a few spots so the smaller cherries, and especially their babies, get a share.
Can Amano shrimp breed in a freshwater tank?
Females can carry eggs and the eggs can hatch, but the larvae need brackish to salt water to develop, so they do not survive in a freshwater tank.
How long do Amano shrimp live?
About two to three years is commonly cited, and many keepers report longer lifespans in stable, well-kept tanks.
Why do Amano shrimp try to escape?
Climbing out is usually linked to a new tank, stress after shipping or a problem with water quality. Test the water, and keep a tight lid on the tank either way.
Our take
Amano shrimp are one of the easiest shrimp to keep and a genuinely useful clean-up crew, as long as you give them a mature, stable, lidded tank, peaceful neighbors and a bit of food beyond algae. Just don't expect a colony: without salt water for the larvae, the group you buy is the group you keep, which for many tanks is exactly what you want.
Sources: hobby care references for Caridina multidentata; species summary and larval-rearing research on amphidromous Caridina shrimp (larval survival under different temperature and salinity, Crustacean Research); manufacturer documentation for sponge filters and shrimp foods; recurring owner reports on r/shrimptank and r/PlantedTank (2024–2026). Checked October 2026.