The Amano Shrimp is widely considered one of the best algae cleaners.
It is hardier than most other freshwater shrimp and can settle into temperate or tropical habitats.
These dwarf shrimp may not not look the biggest, but they do their job very well. These effective little critters nips algae in the bud before it ever gets a chance to become a problem.
If you mix these shrimp in with other popular algae eaters, they can form a productive cleanup crew that will keep your tank in the best possible shape.
Keep reading to learn everything you need to feed, house, and care for your own group of Amano Shrimp.
Amano Shrimp 101
The Amano Shrimp (Caridina multidentata) is a small shrimp that comes from the Atyidae family.
They are best known as algae eaters and a small pack of these shrimp makes the perfect cleanup crew.
Amano Shrimp are native to Japan and Taiwan and live in freshwater as adults. However, while they are young they will stay in the brackish environment they were born into.
You can find them at just about every aquarium supplier.
Individuals usually cost $3-$6 but they are usually sold in groups of 5-10. Very rarely will you find them for sale individually.
Beginners, experts and those in between will all benefit from keeping a group of these enterprising invertebrates!
Amano Shrimp vs Ghost Shrimp
The Amano Shrimp and Ghost Shrimp are two very similar species.
Both are small, clear colored shrimp that are used for cleaning algae. However, there are plenty of differences between the two.
For starters Ghost Shrimp are not in the same genus or family. They come from the Palaemonidae family, which contains mostly marine and brackish water shrimp.
Amano Shrimp are native to East Asia, while Ghost Shrimp occur along the east coast of the United States. You should only keep Amano Shrimp in a tropical or warm temperate aquarium. Whereas Ghost Shrimp can be placed in both temperate and tropical tanks.
- Experience Required: None.
- Nicknames: Yamato Shrimp, Algae Shrimp, Japan Shrimp, Japonica Shrimp.
- Color Forms: Clear with brown markings.
- Size: 1-3 inches.
- Tank Size: Minimum 10+ gallon.
- Tank Temperature: 65°F to 82°F.
- Make wonderful algae cleaners.
- Can be kept by beginners.
- Fit well in small tanks.
- May be hard to acclimate.
- Very difficult to breed.
- Competes for dominance in groups.
Amano Shrimp Care Guide
Amano Shrimp are excellent for any skill level.
They are less sensitive than many other invertebrates and can even handle a bit of waste or turbidity in the tank.
The most important thing is to keep copper, zinc and other metals out of the water.
These highly toxic metals can be introduced through fertilizer or medication for your fish. You will need to use medication that does not contain metals. If this is not possible then you must isolate the medicated fish until the regimen is over.
Apart from metals the other leading cause of death with Amano Shrimp is failure to acclimate to a new environment.
Acclimation should be a careful and patient process.
The drip method is the best way to acclimate an invertebrate to their new home. Place your shrimp in a small container and use a hose to drip water from your tank. Once the shrimp is partially submerged you stop dripping and monitor their reaction.
Then continue to drip water in until the shrimp is completely submerged.
Allow the critter an hour to adjust to the water and make sure the parameters in the container match those in the tank.
If they have no adverse reactions then you can place your shrimp in the tank.
These shrimp are best known as algae eaters.
However they cannot survive on algae alone and will need a balanced diet.
In addition to algae they will eat microbial biofilm, bacteria, decaying plants, detritus and carrion.
You should make sure they have a mix of protein and vegetables.
Start off with a mix of high protein shrimp flakes and algae wafers. You can also include pellets made for bottom feeders.
Use frozen bloodworms and brine shrimp to satisfy their appetite for carrion. Every so often they will also eat their own molts and molts left behind by their tank mates too.
They will eat up any algae that they find in your tank (including particulate algae). Other particles in the substrate will also end up on the menu. Leaves and stems that drop from your plants are fair game too but your shrimp will not munch on or damage any live plants.
Here is everything that they can eat:
- Particulate matter
- Plant material
- Shrimp flakes
- Bottom feeder pellets
- Algae wafers
- Frozen bloodworms
- Frozen microworms
- Frozen brine shrimp
It is quite easy to overfeed a Amano Shrimp.
You will only need to give them outside food about two or three times a week (depending on how much natural food is available in your tank).
Also make sure to clean up any leftovers as this will help to stop overfeeding and also keeps food from rotting and fouling your tank.
During the daytime you will see them spending most of their time hiding under plants and under logs. They will hide more often when it is time to shed their exoskeletons, which happens once a month.
You can catch them climbing on your plants and glass to catch some tasty morsels but they do not venture above the bottom levels. These little scavengers are always searching for food at the bottom of the tank. They graze in the substrate, on plants and on aquarium glass.
Each social group has an established hierarchy and males will compete to maintain their dominance. To curb this aggressive behavior you should keep an equal ratio of males and females.
The potential for aggression will increase if your group is too small. A good sized well balanced group (5+ shrimp) gives everyone a chance to establish their own place in the hierarchy.
Habitat and Aquarium Set Up
Algae is the most important aspect of this shrimp’s habitat.
In the wild they will roam in both freshwater and slightly brackish habitats where algae grows in abundance. Their favorite is planted areas with rocky substrate.
There is plenty of debris lying around for the shrimp to hide in and freshwater plants provide some additional shelter.
To recreate these conditions inside your tank you will need a tank at least a 10 gallon tank.
The water temperature can be as low as 65°F or as high as 82°F, but the best range is between 75-79°F.
PH should be very basic (between 7.0 and 7.5) and the hardness for adult shrimp is 7 to 10 dGH. Adult shrimp need softer water than younger shrimp (who can handle a brackish salinity). An adult will not survive in saline water for very long, neither will a juvenile survive in freshwater.
Algae and biofilm should be allowed to grow naturally in your tank. It is best to let some accumulate before you first introduce the shrimp to the tank. Use a low power filter that generates a moderate current. A hang on back filter is the best option but you can also use a sponge filter and add an air pump for currents.
Do not raise your filter’s power too high though or your Amano Shrimp may be swept up into the intake.
A smooth pebble or cobble substrate encourages algae growth, so use either for substrate.
Decorate the tank with hollowed out logs, driftwood, and other hiding places for your little bottom dwellers. You can also purchase shrimp tubes made out of PVC or clay.
When picking out plants for your tank you should pick those that are good for attracting algae. Both floating plants and leafy rooted plants can be used in this aquascape.
|Minimum Tank Size||10 Gallons|
|Tank Type||Freshwater planted|
How Many Amano Shrimp Per Gallon?
These tiny shrimp are suitable for small aquariums but how many of them can you keep for each gallon of water in your tank?
The best rule for keeping these critters is to add 2 gallons for every individual Amano Shrimp.
To keep these social shrimp happy you will need a group of at least 5.
You will need at least a 10 gallon aquarium for a group of 5 shrimp.
Add an additional 2 gallons for each additional Amano Shrimp.
Breeding Amano Shrimp
Amano Shrimp are extremely difficult to breed.
This is because in the wild they migrate to brackish water to spawn.
To successfully breed these shrimp you would have to replicate these brackish conditions in an aquarium.
You will need a separate tank with a salinity over 15 dGH and a temperature over 70°F. There must be a thick mat of algae growing along the bottom of the tank. While getting ready to breed the parents should be able to survive off of the algae mats, but you can also give them green vegetables.
The female will undergo a molt before mating.
During this time you will be able to see the tiny eggs in her saddle, between her swimmerets.
Once the female is pregnant you will need to simulate an estuarine current in order to get her to spawn. You can use a small air pump to do this.
After 5 weeks of pregnancy the female will lay her eggs. They take 2 weeks to hatch and the larvae emerge as miniature versions of their parents.
The larvae will survive by eating naturally occurring algae and biofilm in the tank. There is no need to give them any outside food.
Amano Shrimp Appearance
At first glance the Amano Shrimp may be rather dull to look at.
However they are a truly complex little critter.
Just like Ghost Shrimp they have a transparent body with visible internal organs. But they also have a pattern of brown spots and stripes.
Their stomach looks like a yellow ball and is the first organ that you can see.
It is just after the mouthparts and just before the heart.
However because the only grow up to 3 inches long you will have to look very carefully to see anything.
The rudimentary brain connects to a long pink nerve cord that travels down the ventral side of the shrimp. The artery, connected to the heart, travels down the dorsal side.
With females the ovary lies between the heart and the digestive gland – this is where the eggs are produced.
As for their external anatomy, shrimp are decapods so their legs come in pairs of 5.
The cephalothorax holds the 5 pairs of walking legs and the segmented abdomen holds the 5 pairs of swimmerets. In addition to the swimming legs, the abdomen holds the telson which allows the shrimp to swim backwards when they needs to.
Their cephalothorax is covered by a thick shell called a carapace and holds all of the appendages of the head.
Males have smaller, thinner bodies and polka dotted patterns.
Whereas females have a rounded abdomen called a saddle (which is used for holding eggs). They are visibly larger and their bodies have stripes or speckles in place of spots.
History and First Sighting
The Amano Shrimp was first discovered by William Stimpson in 1860.
They were initially called Caridina japonica and were commonly known as the Japonica Shrimp.
The species entered the aquarium hobby in 1994 when famous Japanese fishkeeper Takashi Amano introduced it to his aquascapes. After this, they became known as the Amano Shrimp.
Takashi Amano used thousands of these efficient little shrimp in his award winning setups and this inspired fish keepers around the world to seek them out for their own aquariums.
Their popularity exploded in the 2000s when aquarium suppliers marketed them as algae eating shrimp.
In 2006 researchers at the University of Singapore changed the species’ taxonomy from Caridina japonica to Caridina multidentata.
Today they are one of the most common aquarium invertebrates and one of the most popular algae eaters for freshwater aquariums.
Amano Shrimp can live with anything that does not eat shrimp!
They are recommended for a community of peaceful fish and other invertebrates.
If you have other algae eaters in your tank then the shrimp can team up with them to clean even more algae.
Oto and Bristlenose Catfish are very good at helping these shrimp work.
They can live alongside just about any kind of Tetra, including Glowlight, Lemon and Neon Tetras. You can also add Guppies and other small livebearing fish too.
Cory Catfish and Kuhli Loaches are both safe too.
If you are a fan of Barbs then the Cherry Barb is really the only safe option. Other Barbs are known to harass and prey on shrimp.
You can pair them with other shrimp, such as Ghost, Grass, and Cherry Shrimp. Together they will make a very productive cleanup crew.
Nerite, Mystery and Malaysian Trumpet Snails are also safe for a tank full of Amano Shrimp. The shrimp will not harass or pester the snails.
You should avoid any large fish or even smaller ones that are known for eating shrimp.
It is not wise to add these or any dwarf shrimp to a Goldfish tank. Large Plecos and other large Catfish are also out, as are all Cichlids. Tiger Barbs, Tinfoil Barbs, and most other freshwater sharks should be avoided as well.
Keeping Amano Shrimps Together
These shrimp cannot be kept alone.
They must be kept in groups of between 5 and 8 individuals.
Most of the time they will scuttle around the bottom of the tank with others in their group.
They tend to form hierarchies within their social groups and will attempt to dominate each another. To reduce their aggression you should have an even number of males and females in your group.
Species Summary Table
|Other Common Names:||Japonica Shrimp, Yamato Shrimp, Japan Shrimp, Algae Shrimp|
|Scientific Name:||Caridina multidentata|
|Distribution:||Japan and Taiwan|
|Color:||Clear with brown markings|
|Minimum Tank Size:||10 gallons|
|Tank Mate Compatibility:||Peaceful, non-predatory fish|
Should You Keep Amano Shrimp? (Summary)
If your tank has an algae problem then these amazing algae eaters are worth a look.
They will keep your tank clean and become an active part of your underwater world.
Amano Shrimp are one of the most efficient tank janitors that you can get!
Unfortunately though they do not live for very long and they are not easy to breed. But they are affordable and accessible enough for you to buy new populations whenever you need to.
Amano Shrimp may not look big, but they are wonderful in their own way!
How much algae do your Amano Shrimp eat? Let us know in the comments section below…