Bringing your fish home from the pet store: transport and acclimatisation done right
The ride home from the pet store plays out in two acts: a short journey, kept warm and dark, then 30 to 45 minutes of gradual acclimatisation before release. Done well, these two steps prevent the thermal and osmotic shock behind most of the unexplained deaths of the first week.
How do you transport the bag in good conditions?
Ask for a bag inflated with oxygen (good shops do it systematically) and doubled with an opaque bag: darkness calms the fish. Wedge it upright in a cool box or a cardboard box — the water keeps its heat longer and nothing rolls around under braking. In winter, pre-heat the car; in summer, never leave a bag in direct sun or an overheated boot. A standard bag gives 2 to 4 hours of autonomy: make the pet store your last stop before home. Our transport equipment is in the travel and safety category.
How do you acclimatise the fish on arrival?
- Switch off the tank lighting: release happens in soft light.
- Float the sealed bag for 15 to 20 minutes: the temperatures equalise.
- Open it and add a little tank water every 5 minutes, three or four times: the parameters balance out gently.
- Catch the fish with a net to release them, and discard the bag water: it never goes into the tank.
- No meal the first evening: let them explore, lights off until the next day.
Do you need a quarantine before the main tank?
Ideally yes: two to three weeks in a small separate tank reveal white spot and parasites before they contaminate the existing population. Failing that, choose a shop with impeccable tanks and inspect each fish before buying: active swimming, spread fins, a full belly, no marks. Essential reminder: the receiving tank must have been cycled for weeks — never bought the same day, as explained in our dedicated article.
How many fish should you bring home per trip?
Stock in small groups: one shoal or one species at a time, a week apart, to let the filtration adjust to each rise in load. It’s gentler on the budget too — 20 to 40 € per wave — and it respects the capacities calculated in how many fish in an aquarium. The pet store will happily sell you everything at once; your test kit will thank you for declining.
Frequently asked questions
The journey takes over an hour — what should I plan?
A rigid cool box and a well-inflated oxygen bag are enough for up to 3-4 hours. Beyond that, ask for extra inflation and avoid buying large fish at the height of summer.
A fish stays motionless after release — is that serious?
No, it’s normal behaviour for the first hours: hidden, pale, still. Worry only if it gasps at the surface or swims in spirals — test the water immediately.
Is drip acclimatisation useful for shrimp?
Essential, even: shrimp are highly sensitive to osmotic shock. Allow an hour of slow acclimatisation, using airline tubing with a control knot.
This guide is part of Planète Pets’s Fishkeeping universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.