New fish: quarantine and acclimation step by step

A new fish brings color, but it can also bring parasites or diseases you can't see on day one. A few simple steps protect the fish you already have and give the newcomer a better start.

Before you buy or trade

• Ask for real photos of the batch and, if you can, a short video: normal swimming, open fins and no odd spots.
• Ask about identification: species or bred variety, size, approximate age and, if known, the line. Our marketplace asks for that in every listing.
• Think about the group: a very territorial Chipokae is not the same as a calmer Dragon Blood. Read each species' profile before you decide.

The quarantine tank

A separate, simple tank where a new fish spends its first weeks. Many keepers use three to four weeks. It doesn't need elaborate decor:

• A mature filter (for example, a sponge that has been running in your main tank).
• A heater and a couple of hiding spots, like a pipe or a flowerpot.
• Water with the same pH, KH and temperature as the main tank.

During that time, watch whether it eats, how it breathes, and whether spots, clamped fins or flashing against surfaces appear. If something looks wrong, ask someone experienced or a vet who treats fish before medicating.

Acclimation, step by step

1. Turn off the tank light to reduce stress.
2. Float the closed bag for about 15 minutes to match the temperature.
3. Add tank water to the bag or a bucket little by little, for example a cup every 5 minutes, for 30 to 45 minutes.
4. Move the fish with a net. Avoid pouring the bag water into the tank.
5. Don't feed on the first day; let it explore with the light off.

Moving to the main tank

With territorial cichlids, rearranging a few rocks as the new fish goes in helps "reset" territories and spreads out the attention. Watch the first few hours and have a plan B in case of constant chasing.

Log the arrival date and what you saw in My aquarium. And if you have questions, that's what the forum is for.