Who Are Amano Shrimp and Why Did Takashi Amano Make Them Famous?
Amano shrimp, scientifically known as Caridina multidentata, are a species of freshwater shrimp native to Japan, Taiwan, and parts of coastal Asia. They take their common name from the legendary Japanese aquarist Takashi Amano, who introduced them to the planted aquarium world in the 1980s through his Nature Aquarium philosophy. Amano believed that a truly balanced aquarium should mimic natural ecosystems, and he found that these shrimp were unmatched in keeping algae growth under control without chemicals.
What made Takashi Amano reach for these shrimp above all others was their voracious and relentless appetite for algae. Where other shrimp nibble gently, Amano shrimp work as a team, systematically grazing across every leaf, stem, and substrate surface in the tank. Hair algae, thread algae, green dust algae, and even the stubborn green spot algae that clings to glass — Amano shrimp consume them all at a pace that no snail or pleco can match. In a well-stocked shrimp group, you can visibly see algae retreating within days.
In Cambodia and across Southeast Asia, the planted aquarium hobby has grown rapidly over the past decade. Hobbyists in Phnom Penh who have invested in beautiful aquascapes — Java fern walls, carpets of Monte Carlo, or Iwagumi stone layouts — know the heartbreak of waking up to a tank blanketed in hair algae. Amano shrimp are the professional solution. They are not decorative pets that happen to eat some algae; they are working crew members with a job description, and they execute it exceptionally well.
For Cambodian aquarists moving beyond basic fish keeping, understanding Amano shrimp is a rite of passage. These are not beginner shrimp in the sense that they demand pristine water conditions and are less forgiving of mistakes than cherry shrimp. But for anyone serious about a clean, thriving planted aquarium, adding a group of Amano shrimp is one of the highest-return investments you can make in your tank.
- ✦Buy a group of at least 6 Amano shrimp — they are more confident and active in groups and will graze more thoroughly.
- ✦Amano shrimp are most active during dim lighting or just after lights-out. Do not be alarmed if they hide during the day at first.
- ✦Avoid copper-based medications in any tank housing Amano shrimp — copper is lethal to all invertebrates at even low concentrations.
Size Advantage: Why Amano Shrimp Survive Where Cherry Shrimp Get Eaten
One of the most practical differences between Amano shrimp and the more commonly kept cherry shrimp (Neocaridina davidi) is body size. Cherry shrimp typically reach 2.5 to 3 centimeters at most, making them easy targets for almost any fish larger than a small tetra. Amano shrimp, by contrast, grow to an impressive 3 to 5 centimeters, with females consistently reaching the larger end of that range. That extra centimeter of body length makes a significant difference in survival odds inside a community aquarium.
In Phnom Penh fish shops and markets, it is common to see hobbyists make the mistake of adding cherry shrimp to tanks with angelfish, larger tetras, or gouramis — only to watch the shrimp population quietly disappear over two weeks. The fish are not being aggressive in any obvious way; they are simply picking off tiny shrimp whenever the opportunity arises. Amano shrimp are large enough that most community fish treat them with indifference rather than predatory interest. This makes them compatible with a far wider range of tankmates.
Their size also translates directly into algae-eating power. A single adult female Amano shrimp can graze an area roughly equivalent to a credit card every few hours, working continuously. Cherry shrimp, while charming and colorful, simply do not have the body mass to process algae at the same rate. If your planted tank has a serious hair algae problem, ten cherry shrimp will make a small dent over weeks. Ten Amano shrimp will visibly clear the same algae in a matter of days.
For Cambodian aquarists keeping popular community fish like tiger barbs, rosy barbs, or even peaceful but curious fish like rainbow fish, Amano shrimp are almost always a safer choice than cherry shrimp. They hold their own, they do not hide constantly, and they provide genuine algae control rather than occasional nibbling. If you have been hesitant to try shrimp because your fish kept eating them, Amano shrimp are worth a second look.
Tank Requirements: Setting Up the Right Environment in Cambodia's Climate
Amano shrimp prefer a temperature range of 18 to 24 degrees Celsius — noticeably cooler than the 26 to 28 degrees that most tropical fish prefer. They can tolerate up to 28 degrees Celsius for short periods, but sustained high temperatures stress them, reduce their lifespan, and make them prone to disease. This is one of the most important considerations for aquarists in Cambodia, where ambient room temperatures regularly sit at 30 to 35 degrees Celsius throughout most of the year.
In Phnom Penh and other Cambodian cities, keeping an aquarium cool without air conditioning requires deliberate strategy. A fan clipped to the rim of an open-top tank will drop water temperature by 2 to 4 degrees through evaporative cooling — this is one of the most cost-effective tools available. Positioning the tank away from direct sunlight and away from walls that absorb heat during the day also matters significantly. Serious hobbyists keeping Amano shrimp or other sensitive invertebrates in Cambodia often run a small dedicated aquarium chiller, which costs between 80 and 200 USD depending on tank size.
For water chemistry, Amano shrimp prefer neutral to slightly acidic pH, ideally between 6.5 and 7.5. They are more tolerant of slightly alkaline water than many other Caridina species, but they do not thrive in hard, high-pH conditions. Phnom Penh tap water is moderately hard and treated with chlorine, meaning it must always be dechlorinated before use. A quality liquid dechlorinator such as Seachem Prime neutralizes chlorine and chloramine instantly and is widely available from aquarium shops in the city.
The minimum tank size for Amano shrimp is 20 liters, but they do best in 40 liters or more. Larger water volumes buffer temperature swings and maintain stable water parameters more effectively — both critical factors in the Cambodian climate. Live plants are highly recommended, not only because they provide surfaces for biofilm growth but also because photosynthesis contributes to oxygenation, which shrimp require in good supply, especially at higher temperatures when dissolved oxygen levels naturally decrease.
- ✦Use a clip-on fan over an open-top tank to reduce water temperature by 2-4 degrees Celsius through evaporation — affordable and effective in Cambodia.
- ✦Always dechlorinate Phnom Penh tap water with a liquid dechlorinator before adding it to a shrimp tank. Let it sit for 10 minutes after treatment.
- ✦Check water temperature in the evening and again at midday — Cambodian apartments can swing 4-6 degrees between those times, which stresses sensitive invertebrates.
- ✦A substrate of inert sand or aqua soil buffered to slightly acidic pH supports both Amano shrimp health and planted aquarium growth.
How Many Amano Shrimp Do You Need for Serious Algae Control?
The most common mistake aquarists make with Amano shrimp is understocking them. Two or three shrimp in a 60-liter tank look nice but will barely make a dent in a real algae problem. The proven guideline for serious algae control is one Amano shrimp per 4 to 5 liters of tank volume. For a standard 60-liter aquarium, that means 12 to 15 shrimp. For a 100-liter planted setup, you would ideally stock 20 to 25 shrimp during an algae outbreak.
Once the algae is under control, you can reduce the population or supplement their diet so the shrimp remain healthy even without a constant algae food source. Many experienced aquarists keep a slightly lower long-term stocking density — around one shrimp per 8 to 10 liters as a maintenance crew — then increase temporarily when algae returns. This flexible approach balances the cost of purchasing shrimp against effective tank management.
In Cambodia, budgeting for Amano shrimp requires some planning. These shrimp are rarely found in regular Phnom Penh markets and pet shops, which mostly carry cherry shrimp and common fish. When available, Amano shrimp are typically priced between 2.50 and 5 USD per shrimp (approximately 10,000 to 20,000 KHR each), depending on size and source. Stocking a 60-liter tank for proper algae control can therefore cost 30 to 75 USD for the shrimp alone — a meaningful investment that rewards careful tank management.
It is worth noting that Amano shrimp are among the longer-lived freshwater shrimp, surviving 2 to 3 years under good conditions. Unlike cherry shrimp, which breed prolifically in fresh water and replenish their own population, Amano shrimp cannot breed in fresh water. Every shrimp you buy is wild-caught or commercially produced and will not be replaced by offspring. This makes proper care and stable water conditions especially important — losing shrimp to a heat spike or ammonia spike means spending money to restock.
- ✦For an algae crisis: stock 1 shrimp per 4 liters. For ongoing maintenance after algae is cleared: 1 per 8-10 liters is sufficient.
- ✦Add all shrimp at once rather than in batches — a larger group establishes territory and foraging patterns more effectively from the start.
Feeding Amano Shrimp When There Is No Algae to Eat
Amano shrimp are predominantly algae grazers in nature, but they also consume biofilm — the thin layer of bacteria, microorganisms, and organic matter that develops on all surfaces in a mature aquarium. In a well-established planted tank with natural biofilm growth, Amano shrimp can often sustain themselves without supplemental feeding for extended periods. However, in newer tanks or tanks where algae has been completely cleared, supplemental feeding is essential to prevent starvation and ensure the shrimp remain in good health.
The most effective supplemental foods for Amano shrimp are algae wafers, blanched vegetables, and spirulina-based tablets. Hikari Algae Wafers and similar products are widely available in Phnom Penh aquarium shops and provide a balanced nutritional profile that Amano shrimp consume enthusiastically. Blanched spinach, zucchini slices, and cucumber rounds are excellent natural supplements — blanching (briefly dipping in boiling water) softens the vegetable and makes it easier for shrimp to graze on. Remove any uneaten vegetable after 12 to 24 hours to prevent water quality issues.
Spirulina tablets are particularly valuable because they closely mimic the algae-based diet these shrimp prefer. Drop one tablet into the tank in the evening and observe how quickly the shrimp locate and cluster around it — this is one of the most satisfying sights in shrimp keeping. Feed supplementally two to three times per week in a tank with established biofilm, or daily in newer tanks where natural food sources are limited. Overfeeding is a risk: uneaten food decomposes and spikes ammonia, which is extremely dangerous for shrimp.
One feeding practice worth adopting in the Cambodian context is using locally available vegetables. Morning glory (bok la bong), which is inexpensive and widely available in Phnom Penh markets, can be blanched and offered to shrimp. Spinach is also sold affordably at most markets and is a proven shrimp food worldwide. These options make supplemental shrimp feeding accessible even on a modest budget, reducing dependence on imported aquarium products that can be expensive or inconsistently available in Cambodia.
- ✦Feed spirulina tablets or algae wafers 2-3 times per week as a supplement when algae is not available in the tank.
- ✦Remove any uneaten vegetables after 12-24 hours to prevent ammonia spikes that can kill shrimp rapidly.
- ✦Blanched morning glory (available cheaply at any Phnom Penh market) is an excellent and affordable shrimp supplement food.
The Fascinating Reason Amano Shrimp Cannot Breed in Fresh Water
One of the most unique and often misunderstood aspects of Amano shrimp biology is their complete inability to reproduce in a standard freshwater aquarium. Unlike cherry shrimp, which breed freely in fresh water and can quickly establish a self-sustaining colony, Amano shrimp have a larval stage that is entirely dependent on brackish or marine water conditions. When a female Amano shrimp releases her eggs, the larvae that hatch are not miniature shrimp — they are microscopic, free-swimming zoea larvae that require salt water to survive and develop.
In nature, this process works through tidal rivers and coastal estuaries. Pregnant females move downstream toward brackish or coastal areas to release larvae. The larvae develop in salt water over several weeks, eventually metamorphosing into juvenile shrimp that migrate back upstream into fresh water to complete their growth. Replicating this complex saltwater-to-freshwater life cycle in a home aquarium is technically possible but extremely challenging, requiring dedicated breeding setups with live marine phytoplankton, precise salinity control, and weeks of careful management. It is beyond the reach of most hobbyists.
The practical consequence for Cambodian aquarists is important: every single Amano shrimp sold in the hobby is either wild-caught in its native range (Japan, Taiwan, coastal China) or bred in commercial brackish hatcheries specifically designed for this purpose. There is no natural population reproduction happening in home aquariums. This is in direct contrast to cherry shrimp, neocaridina, and most other popular freshwater shrimp, where a single pair can produce hundreds of offspring over a year in a community tank.
This biological reality means Amano shrimp availability in Cambodia is entirely dependent on the import chain. Bangkok is the primary import hub for ornamental fish and invertebrates entering Cambodia, and Amano shrimp are brought in less frequently than more popular species. When a shipment arrives, stock can sell out quickly. Understanding this supply constraint helps explain why ordering in advance from a reliable source — rather than hoping to find them at a local market — is almost always the better approach for serious aquarists in Phnom Penh.
Sourcing Amano Shrimp in Cambodia: Quality, Availability, and What to Avoid
Finding healthy Amano shrimp in Cambodia is genuinely challenging. The main Phnom Penh fish markets — including the popular aquarium vendor clusters near Orussey Market and scattered shops along Street 240 — carry them only occasionally, and quality can be inconsistent. Shrimp that have been in transit for extended periods, held in overcrowded conditions, or exposed to temperature swings during shipping are significantly more likely to die within the first week of introduction to a new tank. Always inspect shrimp carefully before purchase: look for active movement, full translucent bodies, and no visible lesions or cloudy patches.
The most reliable way to obtain Amano shrimp in Cambodia in 2026 is through online aquarium sellers who import directly from Bangkok or source from regional breeders. These sellers typically offer pre-order options, allowing you to reserve shrimp from an incoming shipment and receive them within 24 to 48 hours of arrival — meaning the shrimp spend minimal time in holding conditions before reaching your tank. When ordering online, ask specifically when the last import was, what holding conditions are used, and whether the shrimp have been acclimated to local water parameters.
Pricing through reputable online sellers in Cambodia generally ranges from 2.50 to 5 USD per shrimp (10,000 to 20,000 KHR), which reflects both the import cost and the relative scarcity of quality specimens in the local market. Be cautious of unusually cheap Amano shrimp — at below 1.50 USD per shrimp, the quality or the species identification itself may be questionable. Some sellers in Cambodian markets have been known to sell smaller, younger specimens of other Caridina species as Amano shrimp. Genuine adult Amano shrimp are noticeably large and have the characteristic rows of reddish-brown dots running along their sides.
When you bring new Amano shrimp home, do not rush the acclimation process. These shrimp are sensitive to sudden changes in water chemistry and temperature. The drip acclimation method — slowly adding tank water to the transport bag or container over 30 to 60 minutes — is strongly recommended. Do not simply float the bag and then net the shrimp directly into the tank. In Cambodia's climate, the temperature inside a transport bag can rise quickly, and a careful, gradual acclimation dramatically improves survival rates.
- ✦Request Amano shrimp from sellers who can tell you exactly when the import shipment arrived — freshly imported shrimp have far better survival rates.
- ✦Use drip acclimation over 45-60 minutes when introducing Amano shrimp to your tank, especially in Cambodia where temperature differentials can be significant.
- ✦Genuine Amano shrimp have two distinct rows of reddish-brown or grayish dots along their sides. If the markings look different, confirm the species with the seller.
Building Your Amano Shrimp Team with 4848 One Shop
Amano shrimp are not the easiest invertebrate to keep, but they are among the most rewarding. A healthy, well-fed group of Amano shrimp transforms a planted aquarium from a constant battle against algae into a balanced, self-maintaining ecosystem that looks spectacular and is genuinely satisfying to manage. The key is getting the fundamentals right from the beginning: stable and cool enough water temperatures, properly dechlorinated water, a mature tank with biofilm, appropriate stocking density, and supplemental feeding when natural algae is limited.
For Cambodian aquarists, the extra challenges of heat management and limited local availability are real but manageable. A clip-on fan, a reliable dechlorinator, and a trustworthy source for quality shrimp are the three practical tools that will make or break your Amano shrimp experience in the local climate. With those in place, Amano shrimp are remarkably hardy and long-lived — a group established in a mature planted tank can thrive for two to three years, steadily keeping algae in check throughout.
If you are ready to add Amano shrimp to your aquarium, or if you have tried before and lost shrimp to poor-quality stock or difficult acclimation, the most important upgrade you can make is sourcing from a seller who understands the unique demands of keeping invertebrates in Cambodia. Quality at the point of origin makes an enormous difference in how these shrimp settle and survive.
4848 One Shop is Cambodia's dedicated live tropical fish and aquatic plant specialist, importing quality Amano shrimp and other invertebrates with proper handling and short holding times. Whether you are setting up your first planted tank or expanding a serious aquascape, the team at 4848 One Shop can advise on stocking numbers, tank compatibility, and acclimation for the Cambodian climate. Browse the current stock or place a pre-order at 4848oneshop.zakgt.net and build your algae crew the right way.