Amano Shrimp also known as Caridina Multidentata, Yamato Shrimp, or Japanese shrimp, is a welcome addition to freshwater home aquariums. These hardy shrimp are tireless when it comes to keeping your tank free of algae.

Aquarists value Amano Shrimp as they are useful and low-maintenance. You can keep these industrious algae eating shrimp in a community aquarium or by themselves in a densely planted tank.

If you plan to add the Japanese Freshwater Shrimp to your aquarium, this guide will help you care for them. It contains information on diet, tank setup, ideal tank mates, precautions, and breeding.

Amano Shrimp Stats

Scientific Name Caridina Multidentata
Common Names Amano Shrimp, Japanese Freshwater Shrimp, Japonica Amano Shrimp
Family Atyidae
Origin Japan, Taiwan, Korea
Diet Omnivore
Care level Easy
Lifespan Two – Four years
Temperament Peaceful
Minimum Tank Size 5 gallons
Temperature Range 65 F to 78 F
KH 1 – 10
pH Range 6.5 – 8.0
Flow Rate Moderate
Breeding Egg-layers; difficult to breed in aquariums
Compatibility Peaceful community species
Tank Setup Heavily planted tanks

Amano Shrimp Origins and Habitat

Amano Shrimp are native to Asia, and the first specimens were documented in the Ogasawara or Bonin Islands, south of Tokyo. They are indigenous to Taiwan, Korea, China, and the Yamato freshwater rivers and swamps across Japan.

The algae shrimp is named after Takashi Amano, who established modern aquascaping. He discovered that these shrimp keep planted tanks clean since they eat large quantities of algae. These crustaceans are now an important part of the freshwater aquarium hobby, as they eat even algae that other shrimp don’t.

These shrimp live in large troupes in freshwater rivers and streams where algae grow plentifully on the dense vegetation.

– Fascinating Facts

Japonica Shrimp are unique as they have an amphidromous life cycle. The adult Amano Shrimp live in freshwater; however, they head towards saltwater areas when breeding since the larvae need salty water in the early stages

Once the larvae mature, they return to the freshwater rivers.

Japanese Freshwater Shrimp Appearance

Japanese Freshwater shrimp are amongst the largest dwarf shrimp, growing about 2 inches long. They are translucent light gray with a white or light stripe running down their back from the head to the tail and rows of tiny reddish-brown dots on their sides.

The male and female Amano Shrimp are easily distinguishable, with the female being larger than the male. The speckles on females are long dashes, while the males have smaller, evenly spaced dots. The female shrimp has a saddle or egg nest under her stomach, where she carries her eggs.

Interestingly enough, the color of the dots depends on their diet. Amano Shrimps that eat a lot of plants and algae will have tints of green. This color is very useful in their natural habitat since it helps them blend in with the foliage and hide from predators.

However, when these shrimp eat flakes, pellets, and other food in the aquarium, the spots can be red or even blue.

Amano Shrimp Behavior

Amano Shrimps are peaceful creatures who are quite fearless. You will see them out and about exploring the tank throughout the day.

However, these little shrimps are voracious eaters. They will rush towards the food at feeding time, pushing the others aside to grab it for themselves, with the largest shrimp grabbing it from the smaller ones.

– Amano Shrimp Benefits

Algae-eating Shrimp are hugely beneficial in the aquarium since they are unsurpassed algae eaters and have an efficient digestive system. These shrimp will eat almost any type of algae apart from black beard algae and cyanobacteria.

They are popular among aquarists, as they eat practically all the waste in the tank, whether it is decaying plants, leftover food, dead fish, or even fish feces. The shrimp waste that passes out looks like large grains of black sand, which you can easily siphon out of the tank while changing the water.

Amano Shrimp Care

Amano Shrimp care is not demanding since they are hardy and adaptable. However, it is vital to add these beautiful little creatures to mature tanks. They will flourish in a well-established freshwater aquarium with plants and the algae growth necessary for their well-being.

We suggest you keep Amano Shrimp in a tank that has at least 10 gallons of capacity. They adapt well to single species tanks, but you can easily pair them with the Cherry or Ghost Shrimp. Amano Shrimp are comfortable with a medium flow of water in the tank, as they are accustomed to moderate to strong currents in the rivers they live in.

The lifespan of these efficient little Algae Shrimp can be from two to five years if they receive good care, proper nutrition, and live in the right water conditions.

– Amano Shrimp Tank Setup

An Amano Shrimp aquarium should be large enough for the shrimp to move around freely, so a 10-gallon tank would be the right size to keep a group of five adult shrimp.

Plan your tank to provide these shrimp with many places to explore and hide in when they molt. Using pebbles, small rocks, and even pool filter sand will make the substrate similar to the river beds in their natural habitat. We suggest a dark substrate to enhance the unusual appearance of these transparent little crustaceans.

– Plants That Go Well With the Amano Shrimp

Amano Shrimps live in areas with thick foliage, so you should add plants like Java Fern, Java Moss, Green Cabomba, Indian Almond Leaves, and Malaysian Driftwood. This will help you replicate their natural environment.

Wooden branches will not only make the tank look more natural, but they will also create more resting places for your shrimp to sit on. You will enjoy watching your Japanese Algae Shrimp walking around the aquarium perching on leaves, rocks, and branches, stopping to graze on the algae.

It is crucial to install a filtration system that won’t suck the Japonica Shrimp in and allow them access to the sponge filter to feed on the biofilm and waste that sticks there. An air-powered Foam filter is a good option, or you can use the Hamburg mat. Its large surface will serve as a continuous source of food for these shrimp.

– Amano Shrimp Water Parameters

Amano Shrimp inhabit freshwater streams and rivers, so you need to match the pH, temperature, and hardness of your tank water to the water chemistry in their natural habitat, so that they can thrive in your aquarium.

Water temperature 72 F to 78 F
pH level  6.5 to 8.0
GH  6 – 8 dGH
KH 4 – 10 dKH
TDS 150 – 200

Although Japanese Freshwater Shrimp is a tough, sturdy little species, check the water parameters from time to time, as sudden drops in the temperature and pH levels can be harmful.

Amano Shrimp Tank Mates

Amano Shrimp tank mates should be chosen carefully. These shrimp are very small and peaceful, and they cannot protect themselves. It would be best to remember that they are likely to be eaten by larger shellfish or fish in your aquarium. On the other hand, they will snatch food away from the smaller, ornamental snails since they are quite greedy.

Japanese Algae Shrimp will fit in well with small to mid-sized, peaceful community fish. You could also keep them with shrimp such as Bamboo shrimp and Cherry shrimp, but be cautious of aquarium crayfish or freshwater lobsters, such as Tangerine Lobsters or Hammers Cobalt Blue Lobsters.

You could choose tank mates from among these fish for your Amano Shrimp:

  • Guppies
  • Celestial pearl danios
  • Cardinal tetras
  • Chili rasboras
  • Harlequin rasboras
  • Platies
  • Neon tetras
  • Zebra danios
  • White cloud mountain minnows
  • Octocinclus catfish
  • Cory catfish
  • Tiger barb
  • Discus
  • Bristlenose pleco

However, the following fish will not be suitable tank mates for the peaceful Algae-eating Shrimp:

  • Arowanas
  • Goldfish
  • Knife fish
  • Silver dollars
  • Pacu
  • Oscars
  • Bettas
  • Gouramis
  • Large plecos
  • Jack Demsey
  • Angelfish
  • Jewel cichlid

You may like to keep the Japanese Freshwater Shrimp with other snails. They would be comfortable with Assassin snails, Golden Inca snails, Mystery snails, Ivory snails, Malaysian trumpet snails, Ramshorn snails, and Japanese trapdoor snails.

Amano Shrimp Molting

Amano Shrimp molt, just as all other ornamental shrimp do. Watching Algae Shrimp molt is very interesting. You will know they are preparing to molt when they suddenly stand completely still for an hour or more. When it is time to shed, the old shell separates from the muscle under it.

The shrimp then curl their tail over and over again to crack the old shell. Next, they carefully pull the front half of their body out of the old shell. Once the front is out, the shrimp snap their body backward to release the rest of their body from the old shell.

Shrimps are extremely vulnerable after molting, so they will hide for two or three days until the new shell forms and hardens. Baby Amano Shrimp will molt once a week when they are growing. This frequency reduces as they grow older. An adult shrimp will typically molt once a month.

– Precautions During Molting

Like all ornamental shrimp, Japonica Shrimp will be unable to molt if the water parameters are not correct and, if they cannot molt, they will die. Hence, the shrimp must have sufficient calcium both in their diet and in the water.

We recommend using a GH testing kit to ensure your water’s general hardness levels are within the required range. If the GH is below 6, the shell will not develop and harden. If the shell is too soft, the shrimp cannot break it, and they will die if they are trapped inside the shell.

Amano Shrimp Health Issues

Amano Shrimp are hardy and robust; however, a few things are deadly for these tiny invertebrates.

The first thing you must avoid is copper, which is lethal for these shrimp. Many commercially prepared fish foods, aquarium plant fertilizers, and medications contain copper or copper sulfate. Before you put any product into the tank, you must read the list of ingredients carefully to ensure they don’t contain copper in any form.

The next thing to be careful about is high nitrate levels and ammonia spikes. It would be best to follow regular maintenance and routine water changes of 25 to 30 percent. Heavy metals are also unsafe, so when you’re setting up the tank, do not use lead weights to anchor the plants, and be sure to remove rocks with veins of metal running through them.

The third thing to avoid is salt. While salt is essential for the larvae, adult Amano Shrimp do not tolerate the smallest amount. If you need to add salt to your tank as a treatment, it would be wise to remove these animals first.

Finally, know that a constant supply of CO2 is necessary for the plants in your aquarium to thrive. However, too much CO2 can be harmful to the algae-eating shrimp since it will cause the pH level to drop.

Amano Shrimp Breeding Process

Amano Shrimp breeding is quite complex and involves many steps to follow their natural breeding process. This is why most of the algae-eating shrimp available in pet stores or sold online are caught and imported from their native habitat.

Yamato Shrimp mate in freshwater rivers and swamps. Once the eggs hatch, the mother releases the larvae or Zoea into rivers which carry them to the sea, where they remain for four to six weeks in salt or brackish water. The larvae remain in the sea until their metamorphosis is complete. Then, the Parva or shrimplets return to freshwater.

– How To Breed Amano Shrimps

You will need to follow their natural breeding pattern if you want to succeed. First, you must prepare a small 2-gallons rearing tank for the larvae. Add sea salt to the rearing tank in preparation for the larvae.

The female is ready to breed after molting. Feed the shrimp well to condition them. After the shrimp mate, the female will carry the eggs in her pleopods or swimmerets for three to five weeks. During this time, the eggs will turn from green to a pale yellowish-brown.

It would be less stressful for the berried female to stay in the main tank until the eggs are hatching. Prepare a cup with 1 gallon of water from the main tank and transfer the female there. Once the eggs are hatched, you must transfer the female back to the main tank to prevent her from eating the eggs.

It would be best to transfer the larvae immediately into the rearing tank, or they will not survive. You will need to feed the baby larvae minute amounts of powdered food every five hours. They will remain in this tank for 20 to 30 days until they become juveniles.

The next step is a growing tank in which the water is not as salty as the rearing tank. If you don’t have another tank at your disposal, make a water change and gradually reduce the level of salt to transition the baby shrimp to freshwater. After 40 – 45 days, when you see the baby shrimp swimming forward continuously, they are ready to live in the main tank.

Amano Shrimp Diet

The Amano Shrimp Diet is primarily omnivorous in its natural habitat. These shrimp eat dead and decaying plants and animals. While they eat algae and other debris in the tank, it is important to supplement this with some meaty food.

There is a variety of algae pellets and wafers available at all pet stores. You can offer your shrimp fish food flakes, fish pellets, and shrimp pellets. Frozen bloodworms and brine shrimp are good sources of protein.

Vegetables like cucumber, squash, kale, spinach, and carrots contain natural calcium, which is essential for the shrimp to grow shells. However, you must blanch the vegetables first. It is also essential not to overfeed the shrimp. We suggest you remove the uneaten vegetables from your tank after one hour to prevent the water from getting polluted, as this can upset the water chemistry and cause the pH and nitrates levels to spike.

Japanese Algae Shrimp spend most of their time searching between the plants and the substrate for debris or leftover food. If you have slower fish in your tank, we suggest you scatter food around during feeding time to ensure the other fish get sufficient food since these little scavengers will rush to grab any food they see.

If you provide your algae-eating shrimp with too much other food, they will stop eating aquarium algae, so it is necessary to strike the right balance when feeding them.


Amano Shrimp are excellent residents of any aquarium. These shrimp are undemanding and get along with many other species of fish and shrimp. Let’s see why you may like to get them:

  • Amano Shrimp keep your tank free of algae
  • They are robust
  • These shrimp are quite fearless
  • Copper is very harmful to this species
  • Adult Amano Shrimp do not tolerate salt
  • They keep your tank clean by eating up leftover food
  • These shrimp don’t add waste to the tank as their digestive system is efficient

If you wish for help with your tank maintenance and keep it free of algae, the Amano Shrimp is a great choice.

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