Amano Shrimp (Caridina multidentata): Ultimate Care Guide

Common Name(s)Amano Shrimp
Scientific NameCaridina multidentata
OriginJapan and Taiwan
Temperature65-85°F (18-29°C)
Size2-3 inches (5-7 cm)
Minimum Tank Size5 gallons (19 L)
Food & DietOmnivorous
Lifespan3-5 years
Water pH6.0 to 7.5
Tank MatesAs non-aggressive dwarf shrimp, they will not harm other fish. However, they may become prey to other larger fish.
BreedingMates in brackish water
DiseaseMay be susceptible to fungal, bacterial, and parasitic infections.

How to Care for Amano Shrimp

Amano Shrimp (Caridina multidentata), also known as Algae Eating Shrimp, Yamato Shrimp, and Japanese Shrimp, are one of the most popular Caridina shrimp amongst aquarists. Amano Shrimp make excellent pets for beginners, as they are resilient, easy to care for and are very active, peaceful creatures. Amano Shrimp are good eaters, with a preference for algae (hence their nickname) and are fascinating to observe. Although breeding them is next to impossible, their charm and long lifespan make them a great choice for any fish keeper.

Amano Shrimp (Caridina multidentata)
Amano Shrimp (Caridina multidentata)


Amano Shrimp are a hardy species that live in cool waters, able to tolerate a temperature range between 65°F to 85°F (18°C to 29°C). An aquarium heater may not be necessary for this species, however, it is best to judge case-by-case, depending on the temperature of the room and the general climate. The higher the temperature, the higher their metabolic rate and activity, which may prevent and reduce aquarium algae, though this can lead to a shorter lifespan. Keepers must watch the temperature levels, because sudden fluctuations causes Amano Shrimp stress, weakening their immune system against attacks from parasitic or bacterial invasions. Higher heat is disadvantageous for Amano Shrimp as it affects their molting, decreases the levels of oxygen in the water, and decreases the valuable bacteria colonies. Amano Shrimp facing cooler waters will be lethargic, eat less, delay their growth, and also impact the beneficial bacteria. A thermometer can do wonders for a keeper (apart from choosing an ideal room to keep the Amano Shrimp) and either using a heater/cooler.

Water Parameters

Generally, Amano Shrimp can tolerate hard water, but for the sake of their health they should remain in water with a carbonate hardness around 6.0 to 8.0 dKH. Total Dissolved Solids (TDS) must be at 100 to 400 ppm. Nitrite, Nitrate, and Ammonia levels should be at 0, as wild-caught Amano Shrimp react poorly to these chemicals. Amano Shrimp would benefit from having aquatic plants and changing their water twice a week, since this may reduce the levels of such harmful chemicals. Dechlorinators (also known as “conditioners”) may be added to the water, because Amano Shrimp are intolerant of chemical additives, for example chlorine and chloramines. It is important that keepers do not over-condition the water and instead follow the provided instructions.

Water pH

Amano Shrimp dislike rapid pH drops, therefore it is recommended keepers stick with a pH range of 6.0 to 7.5 – a general neutral level. If an aquarist has soft tap water, a planted substrate with pH-reducing properties would make the water too acidic for the Amano Shrimp. To remedy this, calcium, magnesium or bicarbonate soda needs to be added to bring up the pH. Amano Shrimp cannot bear high carbon dioxide (CO2) levels, which tends to decrease pH levels. This species should never be left in an environment with a pH below 6.0, as they will greatly struggle to survive.

Amano Shrimp Size

Amano Shrimp are one of the larger variety of dwarf shrimp, reaching a maximum size of two to three inches (5 to 7 centimeters). Amano Shrimp can take three to five months to reach their full size, however, this depends entirely on their health.

Amano Shrimp Tank Size

As a general rule, tank size should be determined by the number of Amano Shrimp keepers intends to house. One Amano Shrimp per every two gallons (7.6 L) is a good guide to follow, with a five gallon (19 L) tank being the absolute minimum if tank mates will be added. A

ten gallon (38 L) tank might be the best for Amano Shrimp, just to be on the safe side, giving them plenty of space to move around and live peacefully.

Amano Shrimp Food & Diet

Amano Shrimp are omnivorous invertebrates that consume a variety of matter they find while scavenging for food that can naturally be found in their tank. Keepers must be aware of the fact that while Amano Shrimp are famous for being prolific algae consumers, they still require more than decaying plants to thrive. Amano Shrimp will enjoy being fed two to three times a week, with food such as blanched vegetables (e.g. zuchini, spinach), squash, cucumber, dried pellets/shrimp food (with spirulina and plant ingredients), algae wafers, aufwuchs, moss balls, frozen foods (bloodworms and brine shrimp) and supplements (as and when needed, especially if they lack algae and plant debris). At times they may snack on dead fish or molted exoskeletons, which is perfectly normal. It is important to manually take out uneaten food after an hour, as this will cause ammonia spikes and water contamination, which Amano Shrimp are sensitive to. Amano Shrimp prefer tanks with a decent amount of growing algae, and their meals will need to be adjusted, according to the size of their tank. Keepers must avoid copper as this is toxic to many shrimp species – food and medication labels must be read carefully.

AMANO SHRIMP CARE – Best Algae Eater for Planted Tanks?

Amano Shrimp and Algae

Amano Shrimp favour filamentous algae, and hobbyists can spot them grazing on groups such as Red algae (Rhodophyta), Hair algae (Bryopsis), String algae (debris), Green algae, Green dust algae (GDA), and Green Beard algae. Almost all sorts of algae present in their freshwater habitat will provide them with a suitable food source. If an aquarist wants their Amano Shrimp to eat more algae, they will need to feed them less.

Can Amano Shrimp survive on algae or do I need to feed Amano Shrimp?

Ideally, Amano Shrimp must be fed a nutritious, well-balanced diet several times a week, in addition to the algae that they graze on in their tank. Amano Shrimp need an omnivorous diet, despite their nickname being the “Algae Eating Shrimp.” These shrimp are not picky eaters and will eat almost anything, apart from cyanobacteria.

How much algae can Amano Shrimp eat?

Amongst other species, studies have shown that Amano Shrimp are the most adept at cleaning up algal biomass, in comparison to Red Cherry Shrimp, Nerite Snails, and Siamese Algae Eaters (SAE). Amano Shrimp tend to eat less of Black Beard Algae (BBA) and some cyanobacteria types, but will happily eat other forms of algae.

Will Amano Shrimp eat algae off glass?

Being the superb cleaners that they are, Amano Shrimp will have no issues feeding on Green spot algae, Green dust algae (GDA), and other algae present on glass surfaces. However, hobbyists should be aware that Amano Shrimp do not have the ability to clean the glass in their aquariums, as they lack the anatomical structures needed to achieve this.

Do Amano Shrimp eat hair algae?

Amano Shrimp have no quarrels eating Hair algae (Bryopsis), which is a marine green algae consisting of singular tubular filaments, inhabiting tropical seas worldwide.

Do Amano shrimp eat brown algae?

Amano Shrimp will consume the brown algae (Phaeophyceae) in their tank. This brown algae comes from diatoms, which show up in tanks that are cycling. Generally, this indicates that the water quality is less than ideal. Nevertheless, hobbyists should not panic, as this issue will correct itself over time.

Do Amano Shrimp eat Black Beard Algae?

Amano Shrimp will eat Black beard algae (BBA), but this is not their favorite food. Black Beard Algae are tough to eat, so they will most likely go after other types of algae first. If they are well-fed, they may not eat too much Black Beard Algae in the tank.

Amano Shrimp Lifespan

Amano Shrimp are able to live up to five years, though in captivity they usually survive two to three years. High-quality water and a good diet must be provided, as wild-caught Amano Shrimp have to adjust to their new environment.

Amano Shrimp (Caridina multidentata)
Amano Shrimp (Caridina multidentata)

Amano Shrimp Tank Mates

Amano Shrimp are non-aggressive dwarf shrimp, largely unsuited to inhabit the same environment with larger, predatory species due to their lack of defence mechanism. Tank mates to avoid include: Cichlids, Oscars, Arowanas, Large Plecos, Gourami, and even larger invertebrates (e.g. Cobalt Blue Lobster, Crayfish, Tangerine Lobster).

Acceptable tank mates (apart from other Amano Shrimp) would preferably be: Cherry/Bamboo/ Vampire Shrimp, Bristlenose Pleco, Neon Tretras, Otocinclus/Cory Catfish, Malaysian/Mystery/ Nerite Snails, Trumpet and Ornamental fish (e.g Discus, Barbs). Their tank needs to be large enough to accommodate other species, as well as the Amano Shrimp and all their hiding spots (dense vegetation, caves, PVC tubes).

How many Amano Shrimp should be kept together?

Being the social invertebrates that they are, Amano Shrimp should be kept in groups of at least five to six shrimp.

Can you add Amano Shrimp in a community tank?

Amano Shrimp must be fully mature if an aquarist is looking to add this species to a community tank. They need to be in a large colony of over ten shrimp in order to feel safe and develop the instinct to hide from larger fish. Caution should be exercised when putting Amano Shrimp in a new community tank as there are risks that need to be assessed.

Amano Shrimp and Betta

Bettas can be aggressive and Amano Shrimp are generally vulnerable to them if they are kept in an incorrectly-sized tank. It is recommended that these two species are kept in a tank of over five gallons, with a decent lid and plenty of hiding places for Amano Shrimp. Feeding Bettas regularly may deter them from attacking smaller aquatic animals that are nearby. Thus, with proper precautions, they may theoretically be housed in the same tank.

Amano Shrimp and Goldfish

Keepers should avoid placing Amano Shrimp and Goldfish in the same tank, because Goldfish tend to eat tank mates that are smaller than them. It is best to keep these two species separate for the sake of the Amano Shrimp’s safety.

Amano Shrimp and Guppies

Amano Shrimp and Guppies co-exist well in a tank, provided that they are given everything they need in that shared space. Guppies are insatiable eaters, therefore aquarists need to be prepared when their Amano Shrimp colony decreases. Amano fry are not safe from Guppies and will likely be devoured by them.

Amano Shrimp Tank Setup

Aquarists must make sure that their Amano Shrimp tank is set up with the specific accessories needed to ensure their pets health and safety. Aquarium filter, aquarium substrate, and decor (Aquarium driftwood, caves, aquatic plants) are an absolute must. Being the enthusiastic algae eaters that Amano Shrimp are, planted tanks

are more ideal for this species, though they will require more maintenance. As Amano Shrimp scavenge for food, an Iwagumi formation for the tank would make the most ideal living space for them. The tank should have both light and dark areas, giving the Amano Shrimp plenty of places to feed, hide, and socialise.

How many Amano Shrimp can I keep per gallon?

As a general rule, one Amano Shrimp per every two gallons (7.6 L).

Can I keep Amano Shrimp in a 5 gallon tank?

Depending on the size of the Amano Shrimp colony, a five gallon tank should be an ideal size.

Will Amano Shrimp escape if there’s no lid on the aquarium?

Amano Shrimp are excitable little creatures, with the ability to swim very fast, and it is common to have them jump out of a tank with no lid, especially when being chased by a bigger predator. To keep the shrimp safe from suffocation, a lid placed on top of the tank would be ideal for hobbyists to remember.

How do I acclimate Amano Shrimp into a new tank?

Amano Shrimp must be acclimatised to the parameters of the tank they will be staying in. It is vital that keepers check the current parameters and make appropriate adjustments if they are not ideal. Using the drip method on the Amano Shrimp inside a bowl for three hours is necessary. This process prevents the shrimp from being shocked and endangering them within a toxic environment. Amano Shrimp must be monitored for at least 24 hours following this method.

Amano Shrimp Breeding

Breeding Amano Shrimp in captivity is extremely challenging (even for the most experienced in the hobby) and those who attempt it must be committed to understanding what it entails. Amano Shrimp require brackish water to mate, and need to be transferred back to their original freshwater habitat once the female releases her eggs.

How long do Amano Shrimp hold eggs?

Amano Shrimp females will carry the fertilized eggs in her pleopods for five to seven weeks. During this time she fans the eggs to make sure they are getting enough oxygen and are free of mold, grime, and harmful bacteria.

What are the Amano Shrimp pregnant stages?

A female Amano Shrimp can lay over 1000 eggs, which are glued to her forked pleopods for several weeks, until they hatch into larvae.

How do you raise Amano Shrimp larvae?

The fertilised Amano shrimp eggs will hatch in brackish water, with the larvae needing saltwater to mature. Once the larvae grow into adults, keepers must transfer the them to a tank with appropriate freshwater. It is important to add marine plankton and algae, as this is what Amano larvae feed on.

Amano Shrimp Disease

Amano Shrimp may encounter some dangers within their water, including fungal, bacterial, and parasitic infections. For instance: Planaria (flatworms) are one of the most harmful infestations, releasing tetrodotoxin that will paralyse the Amano Shrimp, allowing the Planaria to consume them entirely. If Amano Shrimp have white fuzz on top of their heads, this means they contracted Scutariella japonica, a parasite that feeds on shrimp plasma and lays its eggs in their gills. Hobbyists must be dedicated when spotting these infestations!

Why is my Amano Shrimp Dying?

Despite being one of the hardiest of invertebrates, Amano Shrimp may easily perish due to human error. This is why it is so important for keepers to do their research and make sure the care being given is suitable for the shrimp. Incorrect water parameters, lack of acclimatisation, improper diet, accidental poisoning, forgetting to recycle tanks and too many water changes can all cause the early deaths of their Amano Shrimp.

Amano Shrimp Molting

Molting is a natural process where the Amano Shrimp’s exoskeleton is shed monthly as it matures. Most shrimp are very fragile after molting and will keep out of sight for a few days, until their outer shell hardens. Female Amano Shrimp will strive to breed as soon as they have finished molting. This species of shrimp typically molt after a water change, thus keepers should avoid disturbing the water too much, as it could lead to stress and fatality.

What to do when Amano Shrimp is stuck in the middle of molting?

There is very little that can be done to help an Amano Shrimp stuck in its molt. At times, the trapped shrimp might be able to wiggle free from the carapace, however, there is always a chance this could fail. Some aquarists have resorted to holding part of the molt with tweezers to allow the Amano Shrimp just enough support to discard its shell. It should be noted that this is very risky, as Amano Shrimp are very vulnerable when being handled.

How to tell if my Amano Shrimp is molting or dead?

Amano Shrimp molts appear very translucent, with a piece of the shell pulled apart, indicating where the shrimp swam out. Molts will also be surrounded by the occasional opportunistic shrimp grazing on them to re-absorb the much-needed calcium. Dead Amano Shrimp change their coloration to a pink/white version of what they previously had, due to the carotenoids present in their body.

Do Amano Shrimp come in different colors?

Amano Shrimp are transparent and normally colourless, with very light pigmentations of grey, brown, green, blue and rust.

Amano Shrimp Price

Because the majority of Amano Shrimp are wild-caught, they are more pricier compared to other species of invertebrates. Amano Shrimp are also difficult to breed, hence their expensive cost, which can set a keeper back $25 per every five shrimp.

Amano Shrimp vs Ghost Shrimp: Similarities & Differences

Amano Shrimp (Caridina multidentata) are native to Japan and Taiwan, Ghost Shrimp (Palaemonetes paludosus) originate from the south-eastern parts of the United States. Ghost Shrimp lack colouration and appear almost completely transparent, apart from some yellow, orange, and green tints from time to time. Both species are non-aggressive and can live together as tank mates, although Amano Shrimp are half an inch larger compared to Ghost Shrimp. Female Amano Shrimp are bigger in size, however, male and female Ghost Shrimp possess no size differences, making it harder to tell them apart. Ghost Shrimp breed faster than Amano Shrimp, although, they tend to live for only one year. Ghost Shrimp mature in freshwater, in contrast to Amano Shrimp that require saltwater. Ghost Shrimp are less costly, priced at an estimate of $1 to $3 per shrimp, versus the Amano Shrimp.