Neocaridina are forgiving shrimp, but they're forgiving within limits, and knowing where those limits sit is most of what keeps a colony alive. This is the reference page we wish every new keeper had before their first shrimp went in: every parameter that matters, the range we hold our own tanks to, and — the part most guides skip — what each number is physically doing inside the animal. Learn the why and the numbers stop being a list to memorise.
Before any of it, the rule that overrides the whole page: stability beats perfect numbers. A colony sitting rock-steady just outside the textbook range will always out-live one being chased towards perfection with constant additions. Keep that in mind as you read every line below.
The numbers at a glance
Here's the full picture. Everything after this table is the reasoning behind it.
| Parameter | Safe range | Breeding sweet spot | Non-negotiable? |
|---|---|---|---|
| Temperature | 18–26°C | 21–24°C (we run 22–23°C) | No, but stable |
| pH | 6.8–7.6 | Same; tolerates 6.5–8.0 if stable | No, but stable |
| GH | 6–12 | 8–12 | Yes — shells depend on it |
| KH | 2–8 | 2–8 | Yes — it buffers pH |
| TDS | 150–250 | 180–250 | No, but watch the trend |
| Ammonia | 0 | 0 | Absolutely |
| Nitrite | 0 | 0 | Absolutely |
| Nitrate | Under 20ppm | Under 20ppm | Keep it low |
Temperature
Cherry shrimp are comfortable anywhere from 18 to 26°C. That wide band is a large part of why they suit UK homes: a tank in a normally heated room sits inside it without a heater for most of the year. We run our breeding tanks at 22–23°C and leave display tanks to find their own level.
Temperature is really a dial for pace rather than survival. Down at 18–19°C a colony ticks over slowly; nudge it into the 21–24°C band and metabolism, grazing and breeding all speed up. If a tank has stalled and you want more shrimp, warming it a couple of degrees is the most reliable lever there is. There's a fuller discussion of the UK angle — when a heater actually earns its place — in do cherry shrimp need a heater in the UK.
Two cautions. Past 26°C, warm water holds less oxygen and shrimp get stressed, so summer heatwaves are a bigger risk in Britain than winter cold. And however you land on a temperature, hold it there. A tank that swings five degrees between a sunny afternoon and a cold night is harder on shrimp than one sitting steady at the top of the range.
pH
Aim for pH 6.8–7.6. In practice Neocaridina tolerate anything from 6.5 to 8.0 as long as it holds steady, and plenty of thriving colonies — ours included — run in the mid-to-high sevens on hard tap water without anyone lifting a finger.
This is the parameter keepers waste the most effort on, chasing a "perfect" pH with chemical adjusters. Don't. A stable 7.8 beats a 7.0 that lurches every time you dose something, because it's the movement, not the value, that hurts. Neocaridina are not Caridina; they have no need for the low, acidic pH that crystal shrimp want, and no need for the active substrates and buffers used to reach it.
Your pH is mostly set by two things you're already managing: your tap water and your KH. Leave the bottle of pH-down on the shop shelf, get your hardness right, and pH tends to look after itself.
GH — the shell-builder
If you learn one number, learn this one. GH, or general hardness, measures the calcium and magnesium dissolved in your water, and those minerals are the raw material a shrimp uses to harden a new shell every time it moults. Target GH 6–12, and 8–12 if you want strong breeding.
Get GH too low — below 6, the common trap in Britain's soft-water regions — and there isn't enough mineral to complete a moult. The result is the failed moults and the white ring of death that end more soft-water colonies than any disease. Soft-water keepers fix this by remineralising up to range; the how is in remineralising RO and rainwater for Neocaridina, and whether your own tap needs it is a regional question we answer in the UK tap water guide.
Too high is a gentler problem. Very hard water, past GH 12–14, can make shells stiff enough that shrimp occasionally struggle to pull free, but it's rare and far less deadly than the soft-water failure. For most keepers GH is a floor to clear, not a ceiling to fear.
KH — the pH buffer
KH, carbonate hardness, is the quiet partner. It doesn't feed the shrimp directly; it stabilises the water. KH is your buffer — the reserve that stops pH drifting or crashing between water changes. Target 2–8.
The danger with KH is a reading near zero, which turns up in soft-water areas and in tanks run on pure RO without proper remineralising. With no buffer, pH can fall off a cliff overnight as the tank's biological processes acidify the water, and a sudden pH crash can wipe a colony by morning. Keep a little KH in the tank and that can't happen.
You rarely need to manage KH on its own. A shrimp GH/KH+ remineraliser raises both together, and in hard-water regions the tap already carries plenty. It's soft-water keepers, and anyone building water from RO, who need to make sure KH doesn't get left at zero.
TDS — the early-warning number
TDS measures total dissolved solids: everything in the water added together, minerals and all. Target 150–250, and 180–250 tends to suit breeding females. On its own a single TDS reading tells you little, because two very different waters can share a number. Its real value is as a trend line.
Watch how TDS moves and it becomes the cheapest early warning in the hobby. A slow creep upward usually means evaporation concentrating the minerals, or overfeeding, or mineral build-up between changes — top up and do a small water change. A sudden jump means something happened: a big dose, a dead shrimp breaking down, something new in the tank. Because a TDS pen costs little and reads instantly, it's the one meter we tell every keeper to buy first. The full case for it is in TDS for shrimp keepers.
Ammonia, nitrite and nitrate
These three are the output of the nitrogen cycle, and the first two are where beginners lose their shrimp. Ammonia must read 0. Nitrite must read 0. Nitrate should stay under 20ppm. Shrimp are more sensitive to ammonia and nitrite than most fish, and any measurable reading of either is an emergency, not a fine-tuning exercise.
The reason new tanks kill shrimp is almost always here. An aquarium needs a fully established nitrogen cycle — the bacteria that turn ammonia into nitrite and nitrite into far-less-toxic nitrate — before any shrimp go in, and that takes several weeks to build. Add shrimp to an uncycled tank and ammonia climbs with nothing to process it. If cycling is new to you, stop and read cycling a tank for shrimp before you buy livestock; it's the difference between a colony and a week of dead shrimp.
Nitrate is the mild one, the end product you manage rather than fear. It builds slowly and is kept under 20ppm with routine water changes and by not overfeeding. Chronically high nitrate won't kill overnight but it quietly suppresses breeding and stresses a colony over time. The safe levels, what causes a spike and how to respond are laid out in ammonia, nitrite and nitrate: safe levels for shrimp.
Stability beats perfect numbers
Everything above resolves into one habit. Pick sensible targets, get the tank to them, and then hold them steady — because sudden change is what actually kills cherry shrimp. A swing in temperature, TDS or pH reads to a shrimp as danger, throws off the timing of a moult, and does more damage than sitting at a slightly "wrong" but stable value ever would.
This is why we're so relaxed about hard tap water in London running a touch high on GH, and so twitchy about big, mismatched water changes. The number matters less than its steadiness. New water goes in dechlorinated, temperature-matched and slowly; changes stay small and regular; and you resist the urge to chase perfection with a shelf of additives. A boring tank is a breeding tank. All of this feeds the wider routine in our cherry shrimp care guide.
Correcting a number without causing a swing
When a reading does come back out of range, the fix is patience, not a big correction. Say your GH is sitting at 4 in a soft-water tank. The instinct is to dose it straight up to 8, but that hands your shrimp exactly the swing you were trying to avoid. Instead, bring it up gradually across several water changes: remineralise the new water you add so each change nudges the tank a little closer, and let it reach range over a week or two rather than an afternoon.
The same logic applies to a high TDS or a creeping nitrate — correct it with a run of small, steady changes, not one dramatic one. The tank should never feel a jolt, even a helpful one. This is the single idea that ties the whole page together: whether you're setting parameters up or bringing them back into line, you move slowly enough that the shrimp never notice.
What to test with
You don't need a laboratory. A liquid test kit covers pH and the nitrogen readings, a GH and KH kit covers hardness, a TDS pen tracks the trend, and a thermometer watches temperature. Liquid kits beat paper strips for accuracy and cost little more over time.
Test often while a tank is new or after any change, then settle into an occasional check once a colony is stable and steady. The goal isn't a spreadsheet; it's catching drift before drift becomes a swing. Once you can read these numbers, most shrimp "mysteries" turn out to be one of them moving when it should have held still.
FAQ
What are the ideal water parameters for cherry shrimp?
Aim for GH 6–12, KH 2–8, TDS 150–250, pH 6.8–7.6 and a temperature of 18–26°C, with ammonia and nitrite at 0 and nitrate under 20ppm. For breeding, tighten temperature to 21–24°C, GH to 8–12 and TDS to 180–250. Above all, hold whatever you land on steady — stability matters more than hitting any single figure exactly.
What temperature do cherry shrimp breed at?
Cherry shrimp live happily at 18–26°C but breed fastest between 21 and 24°C; we run our breeding tanks at 22–23°C. Below about 21°C a colony ticks over rather than grows, so warming a stalled tank a couple of degrees is the most reliable way to encourage breeding. Keep it above 26°C, though, and oxygen and stress become the problem instead.
What GH and KH should cherry shrimp have?
Target GH 6–12 and KH 2–8. GH supplies the calcium and magnesium shrimp use to harden a new shell after moulting, so too little causes failed moults — the main risk in soft-water areas. KH buffers pH and stops it crashing between water changes, which matters most in soft water where KH can sit near zero. A GH/KH+ remineraliser raises both together.
What is a good TDS for cherry shrimp?
Aim for TDS 150–250, or 180–250 for breeding. The single reading matters less than the trend: a slow creep upward usually means evaporation or overfeeding, while a sudden jump means something changed in the tank. A cheap TDS pen is the fastest way to spot drift early, which is why we recommend it as the first meter any shrimp keeper buys.
Is high pH bad for cherry shrimp?
Not on its own. Neocaridina tolerate pH up to about 8.0 and many colonies, including ours, thrive in the mid-to-high sevens on hard tap water. What harms them is an unstable pH, not a high one, so chasing a lower number with chemical adjusters usually causes the swings you were trying to avoid. Get your hardness right and leave pH to settle where it wants.