How to acclimatise new fish safely
By Shan 1 min read
Live fish travel in a sealed bag with limited oxygen and slowly changing water chemistry. Good acclimatisation gives them the best start.
1. Keep it dark and quiet
Open the box in a dim room. Bright light stresses fish that have been in the dark for hours.
2. Float the bag
Float the sealed bag in your aquarium for 15–20 minutes so the temperature equalises.
3. Mix water gradually
Add a small cup of aquarium water to the bag every 5 minutes for 30–45 minutes. For sensitive species like discus or marine fish, use a slow drip instead.
4. Net, don’t pour
Move the fish with a net and discard the bag water.
5. Lights off, feed tomorrow
Leave the lights off for the rest of the day and offer a small meal the next morning.