Acclimate Your New Fish

Understanding the importance of this

Why is this important?

Your new fish needs to adapt to the new environment gradually. The water that the fish is packaged in has a different temperature, pH, and salinity parameters than your tank or its new environment. Fish is very sensitive to even minor changes in these parameters, so proper acclimation is the key to ensuring their successful adding new fish.

Prepare ahead for new fish

Before arrival

Before the fish arrive

  1. Make sure your tank or quarantine tank is set up at least 48 hours ahead with aged water.
  2. Setting up a separated quarantine tank is highly recommended.
  3. Testing the tank’s water condition especially temperature:
    • For Chinese Goldfish:  Water temperature should be around 70 to 80 degree Fahrenheit.

    • For Thailand Goldfish: Water temperature should be around 75 to 85 degree Fahrenheit.

    • For Tropical Fish: Water temperature should be around 78 to 85 degree Fahrenheit depends on the fish.

    • pH (7.0-7.3).

Set up a quarantine tank

A quarantine tank will save lives. Fish can be slowly acclimatized and screened for infectious diseases, sick ones can be medicated and you can even breed in one!

The tank – An empty tank with aged water at least 48 hours prior to arrival. It could be any tank, but 10 – 20 gallons is ideal. It is also depended on the fish size. You don’t want a light in the hood as bright light will stress sick fish and break down medication. The lid also prevents irritated fish from jumping out.

Air – Provide enough air is important for new fish to recover and reduce stress. But, don’t over providing air because it may cause more stress to the fish

Water conditions – It is very important. Our fishes are kept in our facility in the water temperature around 70-72 F. degree. The water temperature may be changed during transportation. Make sure to try your best to match the temperature when transferring the fish into the quarantine tank. The PH of neutral, around 7.0 is ideal.

Chemical usage – Adding extra aquarium salt is recommended. Make sure you follow the instruction on the aquarium salt’s label. Adding water conditioner is highly recommended, products such as SeaChem Prime or API stress coat will help the fish feels more comfortable.

Acclimating the new fish

After arrival

After The Fish Has Arrived

  1. Turn off aquarium lights or switch to dimmed mode. Never open the box in bright light.
  2. Float the sealed bag in the aquarium for 15-25 minutes. You should not be opening the bag at this step. This will allow the water to adjust slowly to the temperature of the tank.
  3. Open the bag  (DO NOT release water inside the shipping bag directly into your tank water) after floating, check the temperature of the water inside the bag and your tank’s water. Make sure the maximum difference is 3 degree Fahrenheit.
  4. Slowly add tank water to shipping bag. We recommend using a small cup, adding slowly every 4 minutes until the shipping bag is full or almost full of water.
  5. Adding a few drops of SeaChem Prime (optional) is recommended to make sure the ammonia level in the bag is under control. Float the bag for an additional 5 minutes.
  6. Slowly lift the bag at the edge and allow water in the tank to travel fully into the bag. Slowly release the fish into the tank.

Expected Behaviors


Some Expected Behaviors After Delivery

Please understand that some of the following situations can happen after the fish being introduced to your new tank:

  1. Bottom sitting
  2. Swimming and/or floating upright

The symptoms mentioned above are very common post-delivery syndromes. If your fish is experiencing them, do not panic, follow out acclimating procedure and the fish will be back to normal after 24 to 48 hours.

IMPORTANT: If those symptoms persist after the acclimation period, contact us immediately to get proper assistances from our fish care team. 

NOTE: Many fish experts have many different methods to acclimate their new fish. However, the fundamental is to stay calm, be patient and slowly adapt the fish. The steps above are our way to acclimate the fish. There are also some other ways to acclimate them that is available on our website.