Amano Shrimp – Caridina Multidentata: A Complete Aquarist’s Guide

Amano Shrimp
Amano Shrimp are becoming more and more popular amongst the aquarists for its relentless freshwater algae-eating ability. Furthermore, they are peaceful, active swimmers, animated, and always in the lookout for food. They eat the leftovers and the debris on the aquarium floor.
They are commonly known as Amano Shrimp, Japonica Amano Shrimp, Yamato Shrimp, Japanese Shrimp, Yamato Numa Ebi, Japanese Swamp Shrimp, or simply Algae Shrimp.
Suppose you would like to know more about this algae eater and how to care, feed, and breed this species continue reading.

Amano Shrimp an Overview:

Description Category
Family Atyidae
Scientific name Caridina multidentata
Origin Japan, Korea, and Taiwan
Type Fresh Water
Color Form Transparent/Greyish
Difficulty Easy
Breeding Difficult
Max. Size 2  inches (5.5 cms)
Life span 2 to 3 years
Temperament Peaceful
Diet Omnivores
Minimum Tank Size 10 gallon (40 liters)
Temperature 18 – 29°C (64 – 84°F), ideal 24°C (75°F)
Acidity 6 to 8 pH
Hardness 4 – 14 dGH
Nitrate >20 ppm

About the Species – Amano Shrimp:

Amano Shrimp, its scientific name is Caridina multidentata. Crustaceans described in 1860 refers to this species as Caridina multidentata was previously known as Caridina Japonica.

Most people believe that Amano Shrimp come only from Japan and the surrounding islands. But they are also seen in the Ryukyu Islands, Korean swamps, Taiwan, and also in Fiji.

Takashi Amano, a track cyclist, photographer, designer, and an ardent aquarist has discovered this species ability to an immense amount of algae. He ordered several thousand of these species with a local distributor in 1982. Since then, these algae bloom control has become popular amongst the aquarists. 

He is also the founder of the Japanese company Aqua Design Amano. He has used and reared this industrious Japanese Swamp Shrimp in most of his tanks. 

Later in 2006, Japonica Shrimp was named after Takashi Amano. 


Life Span of Amano Shrimp:

Amano Shrimp have a lifespan of 2 to 3 years in captivity. Some shrimp breeders claim that they can live up to 6 years. However, if your shrimp survives the first few weeks in your tank, then it is likely to live a long life.

They are no fusser they can adapt to a good range of water conditions as long as they have enough food to eat. They can grow rather quickly in a healthy aquarium environment.

Physical appearances of Japonica Amano Shrimp:

Caridina multidentata

Amano Shrimp can grow up to 2 to 3 inches (around 6 cms) in a well-maintained tank. They are one of the largest dwarf shrimp varieties. 

However, when you buy them from the pet store, they are no more than an inch (about 2.5cms). It is good to buy them smaller as they should adapt to your tank. Smaller does not mean they are unhealthy. 

Japonica Amano Shrimp grow relatively faster in a healthy aquarium setup.

They have a large translucent greyish colored body with a broken line of reddish-brown or greenish points along the sides of their bodies. The colors of these dots vary based on their diets. When they nourish themselves more from algae to leftovers and other debris at the bottom of the tank, the line of dots is in greenish. 

They have large eyes with long sensory wands and a wide translucent tail. 

Shrimps have agile legs. Shrimps are crustaceans, Decapoda (the species that have 10 legs)like crabs and lobsters, have 10 pairs of jointed legs. However, they have different roles depending on the location and the shape of the legs. They are classified into Maxillipeds or the legs of the mouth, Pereiopods, or the legs that walk and Pleopods, or the swimming legs.

Their translucent body helps them to blend remarkably well into your tank and you may not even spot them when they are in their hidings.

How to differentiate from male to female of the species? 

  • The simplest way to identify the male to female of the species is the broken lines along either side of the body; the males have dotted broken lines whereas the females of the species have dashes of broken lines.  
  • The females of the species are larger than the males of the species. 
  • The females have a saddle of bag underbelly, where she keeps the eggs.
  • Females have more rounded belly while the males’ tend to be slender and flat.
  • Also, females have longer pleopods, the swimming legs than the males.

Charlatans of Amano Shrimps in the aquarium trade:

There is a pretty good chance you might end up with lookalikes when you buy them from a pet store. 

Caridina Multidentata is one of the subdivisions of about 300 species that spread across Asia and Africa. With such a massive group of species, with most of them having similar physical characteristics, it is easier for an imposter to be mistaken for our Algae Shrimp. 

There are many Taiwanese and Indonesian variants are doing rounds in the aquarium trade, sometimes even you might as well come across African variants. When you are shopping for Amano Shrimp, be diligent.

How to recognize charlatans?

Well! to begin with, they are shorter than our Japonica Shrimp, and they are essentially lethargic. The reason why Amano Shrimps are popular amongst aquarists is that they are tireless workers. They graze on almost all types of algae, except for cyanobacteria.
Apart from being smaller and lethargic, the imposters breed entirely in freshwater, whereas, our tireless worker does not breed in freshwater.

Amano Shrimp Habitat:

Amano Shrimp are native to Japan, Taiwan, Korea, and China. They live in freshwater, streams, and swamps.

Only the adults live in freshwater, larvae need saltwater, when they mature, they swim to freshwaters.

As far as the water parameters, they can adapt to a wide range of temperature, hardness, and acidity.

Tank Condition for Japonica Amano Shrimp:

The tank set up for Amano Shrimp is pretty simple and straightforward. They are undemanding. If they survive in the first few weeks in your tank, they will likely live a long life. 

They can remold to a wide range of water parameters: temperature range of 18 – 29°C (64 – 84°F), ideal 24°C (75°F), hardness 4 – 14 dGH, and water acidity 6 to 8 pH. As long as the water parameters are not two extremes, that will demand too much from them to adapt to your tank with the exceptions of Ammonia and Nitrite, like any other aqualife.

They are more active in the warmer temperature like any other tropical freshwater fish; however, this will shorten their lifespan as the dissolved oxygen holding capacity drops down with a higher temperature. Whereas, cooler water has a better hold on dissolved oxygen level, but could cost on their immune system.

Regardless, take good care of the CO2 level in the water as it can make the shrimp drown/suffocate to death.

They need a minimum of 10 gallons (40 liters) Tank for 5 Amanos. They should have plenty of hiding places. You can use Java Moss and Riccia fluitans, otherwise commonly known as floating crystalwort. 

You can use some shells, wooden branches, etc. to provide them more shelters. They need plenty of hiding places; you need to keep this parameter while making their habitat.

You should never bring them to a newly set up tank. Always, add them to an established tank. Algae is a must for their livelihood. A new tank will have neither algae nor leftovers.

When it comes to the substrate, mimic Japanese rivers and streams substrates. They are full of pebbles, rocks, and shells.

Filtrations System:

They will hugely benefit from sponge filter media. They nibble the bio-content and waste contained within the foam. Air-powered foam filters are good; Hamburg Matten filters are even better.
Matten filters are good for 10 gallons tank, which involves fixing an entire sheet of 1 and 1and 1/4 inch (3 cms) thick foam within the 2 guided lines. Hamburg matt filter provides an immense filtration surface along with providing a good source of nourishment to our Algae Shrimps and it is economical. You can put one up together all by yourself.

Typical Behaviour:

Amano Shrimps are peaceful by nature, however, when it comes down to the food they are a bit of a street fighter. They actively search for the naturally occurring food within the tank unequivocally. Generally, they follow a pecking order; the largest has the priority.

They become vulnerable just after they molt, which occurs anywhere between 5 to 6 weeks once. They go on hiding; this why they feel comfortable in a heavily planted environment.

Tankmates for Japonica Amano Shrimp:

As we already know that Amano Shrimps are peaceful species, you should choose other peaceful and small to mid-size species as their tankmates. You have plenty of options to choose from:

Cherry Shrimp, Tetras (Small tetras like neon tetra, ember tetra), Stone catfish, Bristlenose Pleco, Cory fish, Vampire Shrimp, Bamboo Shrimp, Ghost Shrimp, Nerite Snails, Guppies, Mystery snails, Danios, Sulawesi snails, Malaysian snails, Tiger barb, etc.

You Caridina is not safe with any aggressive invertebrate or fish.

Bettas, convict cichlids, Jack Dempsey Cichlids, Firemouth Cichlids, Angelfish, Birchir, Blue Acara, Clown loaches, Plecostomus, Oscars, Crayfish, Gourami, large Plecos, Goldfish, etc. are some of the fishes that should not be kept with Japonica Amano Shrimps.

Although Kuhli loach is a peaceful species, should not be kept with Amano Shrimp as they will have our Caridina for a snack.

Keep Amanos at least in a group of 6 to avoid any dominant behavior. As far as possible, maintain an even ratio of males and females of the species. You can also keep them along with the other Shrimps like Ghost Shrimp and Cherry Shrimp.

Amano Shrimp – Diet and Care:


We already know that Amano Shrimp feeds on algae and the leftovers and the bottom. Their ability to clean up the tank is unsurpassed, they are the ultimate squad for cleaning your aquarium tank. 

Amanos are not stunning-looking creatures. However, we keep them for their ability to clean-up potential and not for their looks. They are relentless workers. Considering their size, Japonica Amano Shrimp is much more efficient than any other Shrimps.

Processed foods are strictly prohibited. If they get hooked to the taste of processed food, they will not do serve their purpose for which they are there in the tank.

That doesn’t mean they do not need any diet supplements from you. How many supplements all depend on the aggregates of algae and the waste present in the aquarium tank. 

They are omnivores, their diet should consist of sinking pellets, frozen foods, vegetables.

For frozen snacks, you brine shrimp and blood worms will do the trick.

zucchini, squash, cucumber, etc. can be fed to them. 


  • the vegetables should be blanched before feeding. Uneaten vegetables should be removed before it starts to decompose and contaminate the water.
  • Like most Shrimps, should strictly avoid placing anything made of copper in the tank. It is toxic to most invertebrates. 
  • Many fish foods and medicines contain copper, always read the content labels carefully.

Algae eater:

Algae Shrimp

They eat most types of string algae. They also feed on brush algae and hair algae. Some of these Algae Shrimps even feed on black bear algae.

To have a combination of Amano Shrimps and Nerite Snails or Malaysian Snails will be a good method to control algae in your aquarium tank. Amanos seem to have trouble with spot algae, which the snails will take care of it. 

Amano Shrimp Care:

The Yamato Shrimp does not demand much of your care and time. They are one of the most undemanding freshwaters invertebrates in the aquarium business.


To grow, all the Crustaceans shed their shells periodically. They shed their shells more often when they are young and ensuing their faster growth. An adult Amano molt approximately every 5 weeks. It is hard to keep a track of their molting cycle, though with a group of Japonica Shrimps.
Once they shed their shells, they are more vulnerable to disease and parasites without their armor. They hide in their hideouts, hence while preparing the tank set up you should take care to provide them enough hiding places, such as bushes, shells, rocks, etc.
Do not take the shells out immediately, because, the Shrimps and other living creatures in the tank ingest nutrients from these shells. You may remove the shell after a few hours before it starts to decompose. The decomposition of organic matter produces ammonia and nitrite.


Copper is fatal to the Amanos and other crustaceans. Hence, you must refrain from using anything, which contains copper.
Nowadays, there are many medicines that contain copper in them and much of it has a clear warning that they shouldn’t be used in a tank with Shrimps.

Breeding Amano Shrimp:

Breeding Caridina Multidentata is a tricky one. Amano Shrimp like any other shrimp breed in the freshwater. 

In the wild, the female carries fertilized eggs in her pouch under the tail for 5 to 6 weeks before releasing them into the brackish water. 


Breeding Amano Shrimp

The brackish water will not hurt the adult Amano, but it will destroy the eggs/larvae. The larvae need saltwater to hatch and mature, then they move up to the freshwater. 

To avoid stress levels to the female Cardina Multidentata, the breeding should be kept in the freshwater tank until the female is nearing hatching. 

Prepare a rearing tank of about 2.5 gallons (about 10 liters) ready. When the female is nearing hatching time, move her to the rearing tank as soon as the female releases the eggs move the adult back to the original tank.

At this stage increase the salt level in the tank to about 30 to 34 parts per million (ppm) by adding sea salt. Anything above 40 ppt or any level below 25 ppm will destroy the Cardina Multidentata Larvae. 

However, the required salinity level is still contestable. 

Note: Experienced aquarists suggest, you use commercial salt meant for marine aquaria and not cooking salt to increase the salinity of the water in the rearing tank.

Breeding Amano Shrimps calls for experienced hands.

Is Amano Shrimp suitable for your Tank setup?

If you have a freshwater aquarium tank with peaceful community species, with plenty of vegetation and rocks and pebble substrates, then Caridina multidentata is a great addition to your tank. 

They are relentless workers, who will keep your tank clean, by carefully nibbling algae off the substrates and the tanks. Besides, they keep ammonia and nitrite under the check by eating away all the leftovers in the tank. They feed on the dead organic matter without destroying the healthy plants.

Most Aquarium enthusiasts will keep the Amano Shrimp gladly but dread to breed them. 

There are no other fish or invertebrates as good as Amano Shrimp when it comes to keeping algae under check.

Any queries on the Shrimp keeping leave a comment below alternately contact us here.


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