Most cherry shrimp kept in UK homes don't need a heater, and ours in normally heated rooms run happily without one. Neocaridina are comfortable across a wide temperature band, and a centrally heated living room usually sits right inside it. The heater question is really a stability question: it's cold snaps, overnight dips and draughty spots that catch shrimp out, not the average temperature of a warm room. Here's how we decide, tank by tank.
The temperature cherry shrimp actually want
Cherry shrimp live comfortably anywhere from 18 to 26°C. That band is unusually wide for an aquarium animal, and it's a big part of why they suit British homes — you rarely have to engineer a temperature they'd be happy at, because a heated room hands it to you.
Within that range, temperature sets pace rather than survival. At the cool end, around 18–19°C, a colony ticks over slowly: less grazing, slower growth, little breeding. Warm it into the 21–24°C band and everything speeds up. We run our breeding tanks at 22–23°C for exactly that reason and leave display tanks to sit wherever the room puts them. The full picture of every parameter, and why steadiness outranks all of them, is in our Neocaridina water parameters guide.
Breeding is the part temperature governs most. Below about 21°C, cherries slow right down and a colony can stall for months without ever quite berrying. If you want the steady stream of shrimplets covered in how to breed cherry shrimp, a gentle nudge into the breeding band is the single most reliable lever you have — and the colony growth maths only really work once the tank is warm enough to breed. That's the honest reason a UK keeper fits a heater: not to keep shrimp alive, but to keep them multiplying.
What a typical UK room gives you
A centrally heated room in an occupied UK home typically sits somewhere between 18 and 22°C through the day. That's squarely inside the safe band, which is why an unheated tank in your living room is usually fine on paper. An aquarium also buffers itself: a body of water changes temperature far more slowly than the air around it, so it rides out the short dips a room takes without much movement.
The trouble is that "typically" hides a lot of variation, and shrimp feel the exceptions. A few UK situations regularly fall outside the comfortable case:
- Rooms that aren't heated. Spare bedrooms, home offices, hallways, garages and lofts can sit well below the living-room average, especially once the heating clicks off.
- Overnight setback. Most UK heating is programmed to drop back or switch off overnight. A room that's a cosy 21°C at 9pm can be 15°C by 6am in winter, and that nightly rise and fall is exactly the kind of movement shrimp dislike.
- Windowsills. A tank on a sill bakes in afternoon sun and chills against cold glass after dark — the widest daily swing in the house, and the worst place to stand a shrimp tank.
- Cold snaps and holidays. A week away with the heating off, or a hard frost, can pull an unheated tank down faster and further than the room's usual range suggests.
None of these are about the average being wrong. They're about how far and how fast the temperature moves around it, which matters far more to a shrimp than the number itself.
When a heater earns its place
Put those together and a short list of situations falls out where we'd fit a heater. Reach for one if:
- Your tank sits in an unheated room — a spare room, office, garage or anywhere that regularly drops below 18°C.
- The room swings hard overnight, because the heating goes off and the temperature falls several degrees by morning. A heater holds the floor so the tank can't follow the room down.
- You want the colony breeding, and the room sits below 21°C for much of the year. Below that mark cherries slow to a crawl; a heater set to the breeding band is how you get consistent broods.
- A winter cold snap or time away would otherwise let the tank fall further than its usual range.
Notice that only one of those is really about cold. The rest are about movement. A heater's job in most UK shrimp tanks isn't to add warmth so much as to stop the tank falling away overnight — to hold a steady floor. Sudden temperature change is a genuine stressor: it throws off the timing of a moult, and a mistimed moult is how you get the white ring of death, the failed-moult band that kills more shrimp than a cool tank ever will. Set sensibly, a heater does nothing for most of the day and only wakes when the room drops, ironing out the dips a colony would otherwise have to absorb.
That makes a heater a stability device more than a heat source — the same logic behind adding new water temperature-matched during a water change. Both exist to stop the tank feeling a jolt.
Choosing and setting a heater
If you do fit one, a shrimp tank makes life easy: the volumes are small and you're only topping up a degree or two, so a low-wattage heater is plenty. Match the wattage roughly to the tank size — nano tanks need very little — and don't oversize it, because a powerful heater in a small aquarium overshoots and swings the very temperature you're trying to steady.
A few practical points from our own tanks:
- Preset versus adjustable. Preset heaters that hold a fixed figure around 24–25°C are simple and hard to get wrong. Adjustable ones let you dial in the exact breeding band, which is what we use on tanks we breed from. Either is fine.
- Position it in the flow. Place the heater near the sponge filter's rising bubbles, or wherever the water moves, so the warmth spreads evenly instead of pooling in one corner.
- Guard the shrimp. Curious shrimp rest against warm glass, and the occasional keeper reports one trapped behind a heater. A guard, or simply siting it where shrimp can't wedge in behind, avoids the problem.
- Watch, don't trust. Thermostats fail, and a stuck-on heater cooks a tank fast. Keep a cheap separate thermometer on the glass and glance at it when you feed. Overheating past 26°C is a bigger killer in Britain than cold, because warm water holds less oxygen.
We don't push particular brands — a plain, reliable preset heater sized to the tank does everything a cherry shrimp colony needs.
Running an unheated tank well
If your room stays comfortably in range year-round, an unheated tank is a perfectly good way to keep cherry shrimp, and plenty of our own tanks run that way. The trick is to remove the sources of swing rather than to add heat.
Stand the tank somewhere thermally boring: an interior wall, away from windows, radiators, external doors and draughts. Interior spots barely move in temperature compared with a windowsill or a room's outer edge. A lid helps too, slowing both evaporation and heat loss from the surface.
Then let the water's own mass do the work. A larger tank is steadier than a small one for exactly this reason — more litres mean slower temperature change — so if you're choosing between a 10 and a 20 litre for an unheated room, the bigger tank is the safer bet. Check the thermometer across a full day now and then, especially in deep winter and high summer, and you'll quickly learn whether your room holds steady enough to skip the heater entirely. Most UK living rooms do; many spare rooms don't.
Whether you heat or not, the aim is the same one that runs through all of our cherry shrimp care: a tank that holds steady, so the shrimp never have to brace for a change.
FAQ
Do cherry shrimp need a heater in the UK?
Usually not. Cherry shrimp are happy from 18 to 26°C, and a centrally heated UK room sits inside that band, so a tank in an occupied living room rarely needs heating. Fit one if the tank stands in an unheated room, if the temperature swings several degrees overnight, or if you want reliable breeding — cherries slow right down below 21°C.
What temperature is too cold for cherry shrimp?
Cherry shrimp are comfortable down to about 18°C. They'll survive somewhat cooler, but below that mark they stop breeding and graze less, and sustained cold leaves them sluggish and vulnerable. Cold itself rarely kills them outright — the real danger is a tank that falls fast during a cold snap or overnight, because a sudden drop stresses them far more than a steady, slightly cool temperature ever does.
Can cherry shrimp live at room temperature?
Yes — in most UK homes, room temperature is exactly what our unheated colonies live at. A normally heated living room sits around 18–22°C, which is fine for healthy shrimp. The thing to check is how much your particular room moves: a windowsill or an unheated spare room can swing far more than a stable interior wall, and it's the swing, not the average, that causes trouble.
Will cherry shrimp breed without a heater?
They can, if your room stays warm enough. Breeding picks up between 21 and 24°C — we run our breeding tanks at 22–23°C — and slows to a crawl below 21. An unheated room that holds in the low twenties will produce shrimplets; a cooler one may keep the colony ticking over without ever really growing. A heater set to the breeding band is the fix if broods have stalled.