Fish Acclimation TT97
Published on May 8, 2014

Fish Acclimation - Tech Talk 97

Hundreds of methods have been proposed for acclimation of fish and other aquatic animals. The methods range from just dumping the fish directly into the tank without acclimation (not recommended), to complicated methods of exchanging the water in the fish bag over long periods of time.

Acclimation requires an understanding of key water quality parameters in both the aquarium and the fish bag. In some cases, these water quality parameters may be very similar and little adjustment is necessary before transferring the fish. In other cases, there may be a wide variation in these parameters and care must be taken to acclimate the fish before they are transferred to the aquarium.

The most important tests that should be completed include temperature, pH, ammonia and specific gravity (saltwater tank). Both the fish bag and the aquarium water should be tested before starting the acclimation. If the test results show wide differences between the fish bag and the aquarium tank water, take extra care and time to allow each of these water quality parameters to equilibrate before transferring the fish.

The adjustment may be made in a number of ways. A turkey baster may be used to transfer small volumes of water from the aquarium to the fish bag, slowly replacing the water over time. Another technique is to use an automatic drip method that replaces the fish bag water with aquarium water over a longer period of time.

The method used will depend on how much the key parameters differ between the aquarium water and fish bag. In extreme cases, the fish may require acclimating in a quarantine tank before introduction to the aquarium.

It is important to remember that ammonia levels can build up in the fish bag over time and become increasingly toxic. The toxicity of ammonia is related to temperature, salinity and pH. Higher temperature and pH will result in higher levels of toxic ammonia. For more information see "Water Quality Guide" Tech Talk or contact a Pentair AES technician for assistance.