Cherry shrimp

Water parameters

Tolerated range for this species. Aim for the middle of each band rather than the extremes.

Tank and habitat

Substrate: any.

Behavior

Plant interaction: plant safe.

Feeding

Primarily a biofilm and algae grazer. In a mature aquarium with established surfaces, the colony covers most of its own dietary needs without intervention. Supplement two or three times a week with blanched vegetables (zucchini, spinach, nettle), algae wafers, or commercial shrimp food (Shrimp King, GlasGarten, Hikari Shrimp Cuisine). The species is an omnivore but does not eat live vascular plants. Specialised shrimp foods include calcium, magnesium, and trace minerals that support successful moulting; this matters more than calorie content. A small piece of Indian almond leaf or alder cone in the tank seeds continuous biofilm growth and releases mild tannins that the shrimp graze. Overfeeding is the single most common beginner mistake: excess food fouls the water, and cherry shrimp are more sensitive to ammonia and nitrite than most aquarium fish. Feed only as much as the colony can clear within a couple of hours, and skip feedings entirely on alternating days once the tank is mature.

Compatibility

• Most successful in a species-only tank. Almost any fish will eat shrimplets, and most fish over 4 cm will eat adults given the chance
• Safe tankmates are limited to true nano fish (chili rasbora, dwarf rasbora, sparkling gourami, scarlet badis), small snails (nerite, ramshorn, bladder, malaysian trumpet), and other dwarf shrimp species (Amano, ghost shrimp). Pygmy and dwarf corys are usually fine but may eat newly released shrimplets
• Otocinclus are the gold-standard fish companion: too small-mouthed to threaten adults, focused on diatoms the shrimp ignore, and tolerant of the same water quality
• Do not mix Neocaridina colour morphs. Red, blue, yellow, orange, green, black, and rili all interbreed and the colony reverts to wild-type brown within a few generations
• Copper-bearing medications, fertilisers, or treatments are fatal at fish-safe doses. Read every ingredient list before adding anything to a shrimp tank
• Crayfish, including dwarf species (Cambarellus patzcuarensis 'orange dwarf'), hunt and eat sleeping shrimp at night

Origin and habitat

A selectively bred colour morph of Neocaridina davidi, a small atyid freshwater shrimp native to inland streams, rivers, lakes, and ponds across Taiwan, eastern China, the Korean Peninsula, and Vietnam. Edouard-Louis Bouvier described the species in 1904 as Caridina davidi from specimens collected in the Shanghai area, originally placing it in Caridina. The Japanese carcinologist Ichiro Kubo erected the genus Neocaridina in 1938 (type species N. denticulata, de Haan 1844) to separate a set of land-locked East Asian freshwater atyids from Caridina sensu stricto, and the species was transferred to the new genus. Synonyms appearing in older literature include Caridina denticulata sinensis Kemp 1918, Neocaridina denticulata davidi, Neocaridina denticulata sinensis, and Neocaridina heteropoda Liang 2002. The genus is still under taxonomic revision and some species remain contested. The wild form is mottled brown with fine speckling and excellent camouflage on dark substrates and leaf litter; a 2021 peer-reviewed study by Plichta et al. (Animals 11(4):1071) demonstrated that brown, red, and white colour morphs all prefer dark uniform backgrounds in laboratory choice tests, regardless of the shrimp's own colour. The intensely red cherry, sakura, fire red, painted fire red, and bloody mary trade morphs are the product of decades of selective breeding in Taiwan and China, and every Neocaridina colour morph (red, orange sakura, yellow sakura, green jade, blue dream, blue velvet, blue jelly, black rose, chocolate, rili, snowball) is the same species and freely interbreeds. Mixed-colour tanks revert toward wild-type brown within two or three generations because most morphs are recessive. Females are larger than males (around 3 to 4 cm versus 2 to 3 cm), show stronger colour, and carry an ovary 'saddle' visible through the carapace before egg extrusion. The species is hardier than the related Caridina bee shrimp: cherry shrimp tolerate pH 6.5 to 8.5, GH from 6 dGH upward, KH from 2 dKH upward, and a temperature range of roughly 16 to 28 C. They live longer at the cooler end and breed faster at the warmer end. Feral populations have established in thermally altered waters in Hawaii, Japan, mainland US, Poland, and Germany, mostly from aquarium-trade releases. A 2023 peer-reviewed paper by Maciaszek et al. (Animals 13(10):1616) examined 900 trade shrimp imported from Taiwan and found that around three-quarters host at least one epibiont; the species described and redescribed include Scutariella japonica (a turbellarian in the branchial chambers, often visible near the rostrum), the branchiobdellidan annelid Holtodrilus truncatus, and two species new to science (Cladogonium kumaki sp. nov., an alga, and Monodiscus kumaki sp. nov., a temnocephalan). Most epibionts are harmless commensals; some affect breeding rates and a few are mild parasites. IUCN Least Concern.

Breeding

Among the easiest aquarium animals to breed and one of the most rewarding for beginners. Sexual maturity is reached in roughly 30 days and there is no larval stage: females produce 20 to 35 eggs per clutch and carry them under their swimmerets for 21 to 28 days, after which fully formed miniature shrimplets release into the tank and begin grazing biofilm immediately. Breeding is triggered by the female moulting; she releases pheromones during the post-moult window, and males respond with the well-known 'mating frenzy', fast erratic swimming as they search for the source. In a stable predator-free tank with parameters in range, a starting colony of ten will reach fifty to a hundred animals within a few months without intervention. Sponge filters or pre-filter sponges are essential to keep shrimplets out of pumps. Breeding slows or stops below about 20 C, above 28 C, in unstable parameters, and in tanks with predator fish. Berried (egg-carrying) females are best left alone; the stress of being netted can cause them to drop the eggs. Selective breeding for colour intensity is straightforward in principle: cull the lowest-graded offspring back out of the colony every few generations and the average grade trends upward. Crossing different Neocaridina colour morphs in the same tank produces brown wild-type progeny within two or three generations and is the most common mistake among new keepers.

Common problems

Failed moults are the leading cause of death in cherry-shrimp colonies. The new exoskeleton hardens by drawing calcium and other minerals from the water, so GH below 6 dGH and KH below 2 dKH produce shrimp that can't complete the moult cycle. The signature failure is the 'white ring of death', a visible white band or gap between the carapace and abdomen where the old shell cracked but the shrimp couldn't escape; by the time the ring shows, the shrimp is dead or dying. Maintaining GH 6 to 8 and KH 2 to 5 with a shrimp-specific remineraliser fixes the underlying issue. Copper is acutely toxic to shrimp at concentrations fish tolerate without effect, so any medication containing copper sulphate (most ich and fluke treatments) wipes out a colony in hours, as do many plant fertilisers; read the ingredient list before dosing anything. Cherry shrimp are also more sensitive to ammonia and nitrite than fish, so a fully cycled tank is non-negotiable before stocking. Predator pests can appear in shrimp tanks: planaria (flatworms) eat shrimplets and the occasional berried female; hydra sting and kill small shrimplets. Fenbendazole (No Planaria, Panacur C) treats both at concentrations safe for shrimp. Epibionts (mostly Scutariella japonica) are common on commercial stock and visible as small white worms near the head; they are unsightly more than dangerous, but heavy infestations are sometimes treated with salt or praziquantel dips.

Bioload

Further reading

• Why your angelfish ate your neons
• Blackwater tanks: replicating acidic jungle streams
• GH and KH explained without the chemistry degree