Tiger Shrimp

Tiger Shrimp are the bridge between Neocaridina and the demanding end of Caridina keeping, and they're the species to try when Cherries have become easy and Crystal Reds look intimidating.

They sit in a genuine middle ground: they want softer, slightly more acidic water than Neocaridina, but nothing like the RO-and-active-soil regime Crystal Reds need. In a soft-water area, treated tap water may be usable as-is. In a hard-water area, cutting tap with RO to bring GH and TDS down is usually enough.

Appearance is the draw — a near-transparent body crossed by bold dark bands, with bright orange eyes on the standard form. Against dark substrate and planting they're striking in a way photographs undersell.

They're active, confident feeders and less shy than Crystal Reds, so you actually see them. A 40-litre planted tank with sponge filtration and stable parameters suits a starter colony of ten.

Do not mix with Crystal Reds or Taiwan Bees. All three are *Caridina* and they interbreed, producing muddled offspring that are neither. This is the main practical trap with this species.

Softer and slightly more acidic than Neocaridina; considerably less exacting than Crystal Reds.

GH 4–8, TDS 120–200. In a soft-water area (much of Scotland, Wales, the South West) tap water may land close enough. In a hard-water area, mix tap with RO rather than going to full remineralised RO — Tigers don't need the precision Crystal Reds do, and full RO adds cost and complexity for no benefit here.

KH 1–4. Some buffering, unlike the near-zero KH of a Crystal Red tank. This is what makes them more forgiving: pH doesn't swing the moment something decomposes.

pH 6.5–7.5. Comfortably achievable without active soil, though inert dark substrate plus a few Indian almond leaves suits them well.

Temperature 21–23°C. Like most Caridina they dislike heat; above 25°C expect breeding to slow and lifespans to shorten.

Get a TDS meter. It's the most useful instrument for any Caridina keeping and it costs very little.

Drip acclimatise over 2–3 hours, and expect them to be a little harder to establish than Neocaridina.

Biofilm grazers, like most dwarf shrimp, supplemented two or three times a week with a quality shrimp food.

Indian almond leaves and other botanicals are worth using — mild tannins, a gentle downward nudge on pH, and a steady biofilm supply for shrimplets as they break down.

Feed sparingly. In a lower-KH tank the water-quality consequences of overfeeding arrive faster than they would in a Neocaridina setup, though not as fast as in a zero-KH Crystal Red tank.

Blanched vegetables go down well. Avoid protein-heavy foods, which are associated with bacterial issues in softer water.

Easier than Crystal Reds, for the same reason Cherries are easier than Taiwan Bees: standard Tigers have a largely clear body, so the saddle shows through well.

Look for the pale patch behind the head — developing ovaries, females only. Against a transparent flank crossed by dark bands it's usually quite visible, which makes Tigers one of the more sexable Caridina.

Then the usual: adult females larger, with a deep curved abdomen; males slimmer with a straight underside.

The blue lines are harder. An Orange Eye Blue Tiger or a Royal Blue carries much denser colour, and the saddle becomes as difficult to see as it is on a Crystal Red. If you're buying blues to breed, buy a group of ten or more rather than trying to pick pairs.

One useful side-effect of Tigers being reasonably easy to sex: they're a good species on which to *learn* to sex Caridina, before spending real money on animals where you can't.

Straightforward once the water is right, which is the appeal — you get real Caridina breeding without the Crystal Red learning curve.

No larval stage: eggs hatch after roughly 30 days as independent miniature adults. Clutches of 20–30, a little larger than Crystal Reds.

Moss and leaf litter for shrimplet cover, as ever.

The genetics are the thing to plan around. Tigers come in several lines — standard, Orange Eye Blue Tiger (OEBT), Black Tiger, Royal Blue Tiger — and they interbreed freely with each other *and* with Crystal Reds and Taiwan Bees. Mixing produces offspring that are neither parent and are usually worth less than both.

Keep one line per tank if you care about what you're producing. If you don't, a mixed Caridina tank is perfectly healthy — just don't expect to sell the results as anything in particular.

A colony that stops breeding is telling you about temperature or TDS drift, same as any Caridina.

More flexible than Crystal Reds, because the water they need is closer to ordinary.

Safe: otocinclus, pygmy corydoras, chili rasboras, ember tetras, nerite snails.

Risky: anything above about 4cm will take shrimplets.

Not safe: cichlids, gouramis, loaches, larger barbs, crayfish.

Not with other Caridina — not for safety, but for genetics. Tigers, Crystal Reds and Taiwan Bees all interbreed. This is the compatibility rule that actually catches people.

Neocaridina are a different genus and cannot interbreed with them, but their water preferences pull in opposite directions — Neocaridina want harder water than Tigers do. One population will always be slightly compromised. Workable, not ideal.

Losses in the first two weeks. More common than with Neocaridina. Usually acclimatisation, or a larger TDS gap between the seller's tank and yours than either of you realised. Ask a seller what they run at.

Moulting failures. GH too low. Tigers want less than Neocaridina but not none — below GH 3 they struggle.

Breeding stops. Temperature first, then TDS drift. Both are usually fixable.

Colour fading. Often stress or a recent parameter change; sometimes genetics in a mixed colony.

Offspring that look like nothing in particular. Interbreeding with another Caridina line, almost certainly. Not a health problem — a stock-management one.

Summer heat. Above 25°C they suffer. A clip fan across the surface buys 2–3°C and is worth setting up before it's needed.

Tigers are sold by line rather than on a quality ladder, though within each line the depth and crispness of banding drives price.

Standard Tiger — clear body, dark bands, orange eyes. The hardiest and cheapest. Orange Eye Blue Tiger (OEBT) — blue body, dark bands, striking orange eyes. Considerably more expensive and noticeably less robust than standard. Black Tiger — near-solid dark body, sometimes with orange eyes (OEBT-derived lines). Royal Blue Tiger — deep, opaque blue; the most demanding of the group.

Buy standard Tigers first. The blue lines carry the same trade-off as high-grade Crystal Reds: the selective breeding that fixes the colour costs vigour, so OEBT are meaningfully more fragile and more expensive. Learning your water on standard Tigers is much cheaper than learning it on Royal Blues.

Blue lines photograph inconsistently under plant lighting — ask for images under neutral white light, as with Taiwan Bees.

*Caridina mariae* is native to southern China and northern Vietnam, in streams that sit — usefully — between the two habitats this hobby usually talks about. Softer and more acidic than the hard water Neocaridina come from, but not the extreme soft-water forest streams that *C. cantonensis* needs.

That intermediate origin is exactly why Tigers are the sensible first Caridina. They aren't a watered-down Crystal Red; they're an animal from genuinely different water, and it happens to be water most UK keepers can reach by cutting tap with RO rather than starting from pure RO and an active soil. The care requirement follows the habitat rather than being an arbitrary difficulty setting.

Wild Tigers carry the dark banding the hobby name comes from over a largely clear body. Unlike Cherry or Crystal lines, the wild animal already looks like the thing people buy — the standard Tiger is close to wild-type. The blue lines are the bred ones.

The taxonomy was unsettled for years, which is why older sources are inconsistent. Tigers circulated in the hobby as *Caridina cf. cantonensis* "tiger" — meaning "something close to *cantonensis*, we're not sure" — and were formally described as *Caridina mariae* by Klotz and von Rintelen in 2014, in the same paper that described *C. logemanni* (the Bee Shrimp of Crystal Red fame). The type locality is Guangdong Province in southern China. If you find a care sheet filing them under *cantonensis*, that's why.

That matters practically as well as academically. Being a distinct species from *C. cantonensis* does not stop them interbreeding with Crystal Reds and Taiwan Bees — they do, readily, and the offspring are usually worth less than either parent. The taxonomic separation is real; the reproductive barrier isn't.

Orange Eye Blue Tiger (OEBT) is the best known bred line, developed in the 2000s, and follows the pattern the rest of this hobby will be familiar with: the selective breeding that fixes the blue costs vigour, so OEBT are meaningfully more fragile and more expensive than standard Tigers. Black Tiger and Royal Blue lines came later and sit further along the same trade-off.

As with most Caridina lines, individual attribution is unreliable. The species description is documented; the breeding history is hobby record.