How to Acclimate your New Fish

You must acclimate your fish when it's going into a new aquarium!

Read how to properly acclimate your new fish this Step-by-Step! Acclimating your fish is an important first step for your fish’s health!

The purpose of the acclimation process is to ensure your fish is safely introduced into its new home. The water in the bag that the fish arrives in has different water parameters than your aquarium water such as temperature, salinity levels and pH than your aquarium. By slowly acclimating the fish will reduce any sudden shock and prevent stress on your fish. To successfully introduce your fish to your main display tank, it is recommended that the proper acclimation steps are taken

Things to know before you start your acclimation process:

  • If you have a quarantine tank, it’s recommended to start the acclimating process for that aquarium first. That way you can avoid introducing any diseases or parasites into your main display tank.
  • Do not rush this process as it is critical
  • Acclimation period should be no longer than one hour.
  • Never place an air stone into the shipping back as this will increase pH and ammonia levels.
  • Leave your lights off for at least four to five ours after the new arrival is introduced into the aquarium.
  • Fish will tend to play “dead” so proceed with the acclimating process if this is the case.
  • Corals and invertebrates should never be expose to air, so make sure it is submerged in water.
Your fish is healthier when properly acclimated.

Acclimation Methods

Floating Method

Dripping Method

Step 1: Turn off the aquarium lights.

Step 2: Float the bag on top of the aquarium for approximately 15-20 minutes.

Step 3: Slowly cut open the top of the bag under the rubber-band or metal clip is. Then gently fold the bag over creating a lip like shape. This will allow the bag to float with the bag open.

  • If the specimen is heavy such as a coral, simply place the bag in a bowl with the aquarium water and floating in the aquarium.

Step 4: Add ½ cup of aquarium water into the bag and repeat every four to five minutes until it is full.

Step 5: Remove ½ of the water in the bag by lifting the bag out and discarding the water. Then repeat step 4.

Step 6: Once the bag is full the second time, gently scoop the aquatic live stock out of the bag and place into the aquarium with a net. Make sure you are minimizing the amount of water from the bag into the aquarium.

This has been my favorite method for acclimating aquatic livestock.  

Equipment Needed: airline tubing, and a 5 gallon bucket that is clean.

Step 1: Turn off the aquarium lights.

Step 2: Open the bag and slowly pour the fish/livestock into the bucket.

Step 3: Run a drip line to the bucket by sucking on the end of the airline tube. Once the water begins to run thru the tube, tie a loose knot at the opposite end and place into the bucket to allow a dropping motion into the bucket.

Step 4: Once the water level doubles, discard half and allow the water to refill to so that the water level is doubled once more in the hour.

Step 5: Gently scoop the fish out the bucket and place into the aquarium.

Acclimate your new fish using the drip method.

Other Acclimation Alternatives

Reefing Art - Acrylic Acclimation Box (Hanger) Fish Breeder Nursery Isolation Tank (16"x6"x8")

Innovative Marine Accudrip Acclimator

Sea Side Aquatics Collapsible RF-100C Acclimation Box

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