Amano Shrimp Care Guide: Caridina multidentata for UK Aquarists

The amano shrimp (Caridina multidentata) is the shrimp I recommend to anyone who tried cherry shrimp and had them eaten by their fish, and after 15 years of keeping them I still think they are the most useful invertebrate in the freshwater hobby. Takashi Amano made this species famous for a reason — no other shrimp works through soft green algae, thread algae, and biofilm with the same appetite, and at 5cm they are large enough to survive alongside most peaceful community fish.

This guide draws on data from FishBase^[1] and Seriously Fish^[2], cross-referenced with notes from keeping them through hard London tap water, Yorkshire soft water, and everything in between. Every care parameter here is sourced, and where I give an opinion I will tell you it is one.

We currently stock amano shrimp in single specimens and group packs — browse our amano shrimp range to see what is available for tracked UK delivery.

Where amano shrimp come from

The wild habitat of Caridina multidentata is East Asia — shaded forest streams across Japan, Taiwan, and parts of Korea^[1]. They live in shallow, fast-flowing freshwater with rocks, leaf litter, and plenty of algae-covered surfaces. Water temperatures range from cool in winter to warm in summer, which is why they tolerate a much wider range than most tropical shrimp^[2].

What makes their life cycle unusual is that adults live in freshwater but larvae need brackish conditions. Females carry eggs upstream, hatching larvae drift down to the river mouth where salinity rises, and the juveniles later return to freshwater as miniature adults. This amphidromous cycle is the reason they simply cannot breed in a home aquarium without dedicated brackish rearing.

Understanding this background explains their behaviour in the tank. They want oxygen-rich water, surfaces to graze, and stable conditions — and they cope well with the temperature swings typical of UK rooms.

Tank setup

Size and layout

The practical minimum is 40 litres for a small group, though I would recommend 60 litres for anyone keeping them alongside fish. Amanos spend almost all their time on surfaces — substrate, wood, rocks, plant leaves — so a longer tank with more footprint beats a tall one every time.

They need vertical surfaces too. A tank with driftwood, stone, and tall plants gives them far more grazing area than a bare-bottomed tank of the same volume. In a mature planted tank they are genuinely one of the most visible and active residents.

Stocking suggestions

Water parameters

The accepted temperature range is 18-28 degrees C^[1], which is wider than most tropical species. I run mine at 22-24 degrees alongside tropical community fish, which suits everyone. They tolerate brief dips into the mid-teens and brief spikes to 28 degrees, but stable is always better.

pH should sit between 6.5 and 7.5, with moderate hardness of 3-15 dGH^[2]. This is a broader tolerance than cherries, which is one reason amanos are easier in typical UK tap water. Ammonia and nitrite must read zero — shrimp are less tolerant of nitrogen cycle wobbles than most fish.

The honest truth is that amanos handle stable parameters better than chase perfect ones. A tank that sits at pH 7.4 every day is fine. A tank that swings between 6.8 and 7.6 because you are adjusting things will stress them out and cause failed moults.

Filtration

Gentle to moderate flow works best. A sponge filter is ideal for dedicated shrimp tanks, while covered internal filters or pre-filtered hang-on-backs work well in community setups. The critical point is protecting the intake — uncovered intakes trap moulting shrimp and kill them. Fit a fine foam pre-filter or sponge guard, always.

Amanos appreciate well-oxygenated water. A gentle air stone or filter outlet angled across the surface gives them the dissolved oxygen they need, especially in warmer months.

Substrate and decor

Dark sand or fine dark gravel makes their translucent bodies and reddish dots pop against the substrate. Any inert substrate works — they are not fussy like some Caridina shrimp that need active soil.

Driftwood, stone, and dense planting are essential. They spend hours working through moss, picking at leaf surfaces, and grazing biofilm off wood. Java moss, Microsorum, Cryptocoryne, Anubias, and Bucephalandra all give them grazing surfaces while providing cover for moulting. Add some botanicals — Indian almond leaves, alder cones, dried oak leaves — and you will see them graze on these too.

Lighting

Moderate lighting suits them fine. They are neither photophobic nor sun-loving — they adapt to whatever the tank needs for plant growth. In brighter tanks they tend to hide during peak daylight and become more active in the evening, which makes early morning and late evening prime shrimp-watching times.

Feeding

The great thing about amano shrimp is that they largely feed themselves. In a mature planted tank with visible algae and biofilm, they need very little supplementary food. That changes as they work through the algae and once the tank is mostly clean.

Daily approach

If the tank has visible green algae, diatoms, or hair algae, feed sparingly — maybe once every 2-3 days. Once the tank is spotless and they are clearly grazing through the day, offer small sinking foods every other day. Quality shrimp pellets, algae wafers, or blanched vegetables are all good.

Supplementary foods

Blanched courgette slices, cucumber rounds, spinach leaves, and nettle are all amano favourites. Boil for 60 seconds, cool, then drop in. They will cluster on it within minutes. Remove any uneaten veg after 12 hours to prevent fouling. For protein, occasional frozen daphnia or bloodworm works well, especially when females are carrying eggs.

Feeding tips

Overfeeding is the main mistake. Amanos rush food aggressively, which makes them look hungrier than they are. In a community tank they often grab food from fish, and the leftovers foul the water. Feed only what they finish in an hour or two.

Calcium matters for moulting. Mineral-rich water, the occasional cuttlebone fragment, or a shrimp-specific mineral supplement all help. And always leave a shed moult in the tank — the shrimp will eat it back for the calcium.

Appearance and varieties

The adult amano shrimp is a slender, translucent grey-green shrimp reaching 4-5cm in length^[2]. Rows of reddish-brown dots and short dashes run along each flank, and a faint pale stripe runs from head to tail on the dorsal surface. Under good lighting, healthy adults look subtle rather than showy — closer to a piece of driftwood than a decorative fish.

Females grow larger and fuller-bodied than males, often carrying a visible saddle of developing eggs behind the head. Males are slimmer and slightly smaller. The dotted pattern along the flanks tends to be more dash-like on females and more dot-like on males, though this is subtle.

Unlike cherry shrimp, there are no selective colour morphs of amano shrimp. What you see in the shop is what you get. If you want bright red, blue, or yellow shrimp, cherry shrimp and their Neocaridina cousins are the colourful alternative. Amanos are chosen for function — their beauty is in movement and constant activity across the aquascape.

How they compare to similar species

The question I get asked most is amano shrimp versus cherry shrimp. Simply put: amanos are bigger (5cm versus 3cm), better algae eaters, hardier, and more suitable for tanks with small fish. Cherries are smaller, brightly coloured, easier to breed at home, and more vulnerable to predation. If you have a planted tank with tetras, amanos are the safer choice.

Ghost shrimp (often sold cheaply in the trade) are a different animal entirely — usually a mixed bag of species with variable temperament and size. Amanos are the more reliable pick for planted tanks and aquascapes. Vampire shrimp are filter feeders that need very different care, and bamboo shrimp have similar requirements to vampires.

Tank mates

Amano shrimp are peaceful, non-territorial, and large enough to coexist with most community fish^[2]. Their 5cm size is the main advantage over cherries — most small fish simply cannot swallow a full-grown amano.

Good companions

• Neon tetras — the classic pairing in planted tanks
• Ember tetras — too small to bother adult amanos
• Corydoras catfish — completely safe bottom-dwellers
• Otocinclus — gentle algae graziers with complementary diet
• Honey gouramis — peaceful mouth too small to be a threat
• Nerite snails — share similar non-breeding amphidromous biology
• Cherry shrimp — coexist fine, though amanos will compete for food
• Harlequin rasboras, rummy-noses, kuhli loaches — all compatible

Species to avoid

Anything with a mouth big enough to swallow a 5cm shrimp. Angelfish, gouramis over 10cm, most cichlids (including discus), and larger barbs will eat them eventually. Puffers, crayfish, and predatory loaches are immediate trouble. Goldfish are a definite no — they are opportunistic and produce too much waste for shrimp water quality.

The betta question

Amanos are actually one of the better shrimp options for a betta tank. Their size makes them too large for most bettas to swallow, and they are fast enough to escape curious prods. I have kept them with calm male bettas in heavily planted 40-litre tanks without issue. With aggressive bettas it is still a gamble — a determined betta can harass even large shrimp to death. As always, know your betta.

Breeding in community tanks

Females will carry eggs in any tank with healthy adults, but the larvae will not survive in freshwater. You will sometimes see a berried female for several weeks — it is completely normal and no cause for concern. The eggs simply never develop into shrimplets without brackish rearing.

Breeding

Let me be upfront: breeding amano shrimp at home is a serious project, not a weekend hobby. The adults are easy to keep and will readily produce eggs, but the larvae require a separate brackish rearing system with precise salinity control. If you just want shrimp that breed easily, buy cherry shrimp instead.

Why freshwater breeding fails

Amanos are amphidromous. Adults live in freshwater, but larvae need brackish water (specific gravity around 1.015-1.020) to develop. Hatched larvae released into pure freshwater die within 5-7 days, usually from osmotic failure before they even finish their yolk sac.

The basic process

If you want to attempt it: a female carries eggs for 4-6 weeks in freshwater. When hatching is close (eggs turn from green to clearer), move her to a larval trap, or time hatching and transfer larvae to a prepared brackish tank. The brackish tank needs marine algae (phytoplankton cultures), careful salinity, and impeccable cleanliness for around 5 weeks, during which larvae pass through multiple zoea stages. Once metamorphosed to post-larvae, gradually freshen the water over 2-3 weeks to transition them back to fresh.

Published success rates are low even among experienced breeders. Unless you specifically want to tackle this as a project, enjoy the adults for what they are — the best algae eaters in the hobby — and buy more when the originals reach end of life.

Health and molting

Healthy amano shrimp are active, constantly grazing, alert to movement, and moult successfully. If your shrimp are hiding constantly, refusing food, or lying on their side without moulting, something is wrong.

Molting

Moulting is the single most important biological event in a shrimp's life. Every few weeks the shrimp splits its old exoskeleton along the back and crawls out — you will find the empty shell looking like a ghost shrimp. This is completely normal. The freshly moulted shrimp will hide for 12-48 hours while its new shell hardens.

Always leave the moult in the tank. The shrimp will return to eat it back — the calcium from the old shell goes into building the new one. Removing it wastes a valuable resource.

Failed moults are the main cause of sudden adult deaths. They happen when water is too soft (not enough calcium), when parameters swing suddenly, or when the shrimp is stressed. A dead shrimp stuck half-in-half-out of its old shell is a failed moult. The fix is stable, mineral-rich water — not medication.

Copper toxicity

This deserves its own section because it kills more amanos than any disease. Copper is lethal to invertebrates at trace levels. Sources to watch for:

• Fish medications — check every label, including plant-safe algaecides
• Snail treatments — most contain copper, do not use
• Plant pesticides on new aquarium plants — quarantine all new plants for 1-2 weeks
• Very old UK copper plumbing — run the tap for 30 seconds before refilling
• Brass fittings on some aquarium equipment

If you must medicate fish, move the shrimp out to a separate hospital tank first.

Common problems

Bacterial infections occur on damaged tissue, usually after a failed moult. Fungal growth is rare but can appear on dead eggs or injured individuals. Planaria (small flatworms) can sometimes appear in shrimp tanks and prey on very small shrimplets, though they are no threat to adult amanos.

Prevention

Good husbandry solves 90% of shrimp health issues. Keep parameters stable, avoid copper, provide mineral-rich water, feed appropriately, and quarantine new arrivals. Test for ammonia and nitrite — both should be zero. Nitrate should stay below 20 ppm for long-term colony health.

Behaviour

Amano shrimp are active, curious, and almost always visible once settled. In a mature tank they spend the day climbing over every surface — wood, rocks, leaves, substrate — picking at biofilm and algae. They are surprisingly bold, often coming out at feeding time to grab food from under the nose of larger fish.

After a moult, individual shrimp hide for a day or two while their new shell hardens. Do not panic if one goes missing for 48 hours — check behind the wood and in the moss before assuming the worst.

They are also extraordinary escape artists. Amanos can climb filter cables, airline tubing, and any vertical glass surface. A tank without a sealed lid will eventually lose shrimp to the carpet. I seal every gap with black foam tape, including around filter cables, heaters, and the back strip of the lid. This is the single most common preventable death in home aquariums.

Group behaviour is looser than schooling fish but social enough that they will often gather on the same piece of wood or veg. A group of 5+ tends to be more confident and visible than a single shrimp, which is why I recommend 3+ as the practical minimum and 5+ as the sweet spot.

UK delivery and acclimation

We ship amano shrimp across the UK with insulated packaging and seasonal heat packs to protect against temperature drops during transit. Orders are dispatched Monday to Wednesday for tracked delivery, keeping time in the box as short as possible.

When your amano shrimp arrive, float the sealed bag in your aquarium for 15 minutes to equalise temperature. Then drip-acclimate slowly over 45-60 minutes — shrimp are more sensitive to osmotic shock than fish, so take your time. I use airline tubing with a loose knot giving about 2-3 drops per second. Once the bag volume has roughly tripled with tank water, net the shrimp out gently and release them into the tank. Do not pour the transport water into your display tank.

Newly arrived shrimp may hide for 24-48 hours before becoming active. That is completely normal. Leave the lights dim and avoid feeding for the first day. By day two or three they should be out and grazing.

Amanos are hardier than cherries in transit but still need proper acclimation. Skip the drip and you will lose some to the parameter shock, even from water that is technically "similar" to the bag.

Why buy from us

We hold and observe all shrimp stock before dispatch. Every amano we send out has been feeding, moulting normally, and showing active grazing behaviour. We do not ship shrimp straight from the wholesaler — they are settled and ready.

Each order is packed specifically for invertebrate transport: insulated box, oxygen-enriched bags, and heat packs in cooler months. Tracked delivery means your shrimp spend the minimum time in transit.

If you are setting up a new planted tank or adding an algae team to an existing community, our group packs — browse our amano shrimp listings — are the most practical way to establish a working shrimp colony from day one.

Answers to common questions

How many amano shrimp per litre?

Roughly one shrimp per 4-5 litres in a mature tank with visible algae. A 40-litre tank comfortably supports 8-10 adults, and a 60-litre tank takes 12-15. Understock initially and add more once you can confirm the tank has enough biofilm to support them.

What is the lifespan of an amano shrimp?

Typically 2-3 years, with individuals occasionally reaching 5 years in well-maintained tanks. Most shrimp arrive as sub-adults, so the clock is often already ticking. A shrimp that dies after 18 months in your tank probably lived 2+ years total.

What are the best tank mates for amano shrimp?

Neon tetras, ember tetras, corydoras, otocinclus, honey gouramis, and nerite snails are all excellent. Avoid angelfish, cichlids, large gouramis, and any predatory fish. Small bettas work with caution.

Amano shrimp vs cherry shrimp — which should I choose?

Amanos for algae control and community tanks with small fish. Cherry shrimp for colour and home breeding. Amanos are bigger (5cm vs 3cm), harder working on algae, and safer around peaceful fish. Cherries are brighter and breed readily in freshwater.

Do amano shrimp breed in freshwater?

No. Adults will produce eggs in freshwater and females carry them under the tail for weeks, but the hatching larvae need brackish water to survive. Without a dedicated brackish rearing system, the larvae die. It is the same biology as nerite snails.

Are amano shrimp sensitive to copper?

Yes — extremely. Copper kills amano shrimp at trace levels. Never use copper-based medications, snail treatments, or algaecides in a tank with shrimp. Check every label. Move shrimp to a hospital tank if you need to treat fish with any copper-containing product.

Why do my amano shrimp keep escaping?

Because they can. Amanos are exceptional climbers and will find any gap in the lid, around cables, or over the back strip. Seal every gap with foam tape. Check the lid sits flush. Look behind and beside the tank occasionally — dried shrimp are a grim but common find.

Do amano shrimp eat hair algae?

Yes, better than any other shrimp. Young, soft hair algae and thread algae are their favourite foods. Long established hair algae is harder for them to tackle — trim it back first and they will mop up the regrowth. They also eat diatoms, soft green film, and most biofilm.

What temperature do amano shrimp need?

18-28 degrees C is the full tolerance range, with 22-24 degrees being the comfortable middle for most UK tanks. They cope with seasonal swings better than cherries, which makes them a practical choice for homes without tight temperature control.

What tank size do amano shrimp need?

40 litres minimum for a small group, 60 litres for a community tank with fish. More surface area is always better than more volume — think wood, rocks, and plant leaves rather than sheer water depth.

Why is my amano shrimp lying on its back?

Either moulting or dying. Look for a shed exoskeleton nearby — if you find one, the shrimp is moulting and will recover within hours. If there is no shell and the shrimp is unresponsive, it is likely dead. Sudden deaths usually trace back to copper exposure, a big parameter swing, or a failed moult from soft water.

Are amano shrimp good for beginners?

Yes, with the caveat that the tank must be properly cycled. They are the hardiest freshwater shrimp in the UK trade, tolerate a wider parameter range than cherries, and survive most beginner mistakes — with the important exceptions of copper poisoning and escape. Cycle for 4-6 weeks, seal the lid, keep copper out of the tank, and they will thrive.