How To Acclimate Fish

Whenever people pass through a pet store in the market, some get excited to look for a new pet to add to their home. One of those pets is fish. When you buy a new fish, it is in a plastic bag with water and oxygen.

But, it becomes a common scenario for a fish to die in just a snap after being immediately transferred to the home aquariums. Due to these instances, many fish owners always blamed the pet store for having poor health and maintenance of the fish they sell.

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This sudden death of fish is due to improper conditioning. Pet owners must know the proper process on how to give enough time for the fish to adapt to a new environment, especially to the temperature, oxygen content, and other nutrient levels of water. This process is called fish acclimation.

You will learn about to learn two ways on how to acclimate fish in this short read. You can also expect to learn how to utilize these fish acclimating methods after reading the article. Let’s get into it!

Fish Acclimation With The Drip Method

Check out the steps on how to acclimate fish using the drip method:

Place The Plastic Bag In The Aquarium

Before starting the acclimation of fish, there should be a complete setup of the aquarium with all the necessities or equipment needed.

Place the plastic bag in the aquarium for 20-30 minutes until it floats on its own. Make sure that the knot of the bag is tightly closed. This process is called temperature acclimation. It will help the new fish to adapt or adjust to the temperature of the water in the tank or aquarium.

Add Water To The Plastic Bag

In adding water to the bag, open the plastic bag, get a half cup of water in the tank, and slowly add it to the bag. Repeat the process every 15 minutes.

This gradual process allows the fish to adapt to the change to the water temperature and the oxygen content, other nutrient levels, and even to sounds. It will also prevent the fish from contamination from parasites and diseases.

Get A Bucket

After adding water, you will need a bucket where you will pour the contents of the plastic bag. The bucket must be clean and big enough to accommodate the content. Slowly lift the bag and gradually pour the content into the bucket.

After pouring, check if there is enough water in the bucket, and the fish must be fully immersed in the water, and it is not flapping around.

Setup the Siphoning Tube

Put one end of the siphoning tube in the aquarium down to the bucket with a drip rate of 3 to 5 drops per second. It will let the water flow automatically. If it is already correctly set, make the process work until the water in the bucket doubles.

After siphoning, remove half of the half water in the bucket. You may use a cup to avoid draining the fish. Then repeat the siphoning process until the water level doubles.

Transfer The Fish

It is time to transfer the fish to your aquarium. Using a clean plastic bag, slowly scoop the fish out of the bucket and gently pour it into the aquarium. Remember to take some extra caution in transferring the fish into the aquarium.

Fish Acclimation With The Floating Method

Aside from the drip method, you may also use the floating method of acclimating your fish. Here are the steps you should follow:

Turn Off The Aquarium Lights

If there are lights around the aquarium, it is advised to turn all the lights off to help the fish to adjust because lights can give unnecessary trauma to the fish.

Place The Bag Inside The Aquarium

Place the bag in the tank, then roll the top part of the plastic bag for five to six turns, commonly sealed by a rubber band. With this, it traps the air in the rolls that will make air pockets in the plastic bags, which will make the bag float on its own. This process must not take more than 30 minutes.

Pour Water From The Aquarium

After a few minutes of floating, slowly pour water from the aquarium into the plastic bag. Repeat the step every 15 minutes until the plastic bag gets full. It will help to even out the temperature, whether it is cold or warm.

Inspect Water Quality

Have time to check the quality of water to ensure that it is suitable for the fish. Regularly testing the ammonia, alkalinity, hardness, pH, nitrate, nitrite, and temperature is highly advised to maintain its correct levels. Always check the pH level of the water in the bag to balance the temperature.

Check Water Temperature

Be sure that the temperature and pH of the water in the bag are the same in the aquarium. Do not pour the water from the plastic bag into the tank or aquarium directly. When removing the fish from the plastic bag, use a net or mesh, ensuring their fins do not get caught on it.

Observe The Fish

After adding the fish to the aquarium, be mindful to observe them after acclimation. Some fish might become weak because of some factors such as inadequate care from the pet store and stress due to transportation.

During the observation, give the fish enough time to adapt to their new home.  Pet owners can provide around 24 hours to get used to it because some new fish might become uneasy or anxious in their new tanks.

Feed The Fish With Small Portion

When feeding the new fish, start with a small amount of food. Do not hurry them to eat a lot because they might not eat it or ignore it.

Then it becomes a waste in the water, which can cause diseases and parasites that will lessen the survival rate of the fish. After some time, new fish are already acclimated to their new community tanks.


In conclusion, a thorough and careful acclimation process will let your new fish adapt gradually. It will also give the chance to survive longer. But as a pet owner, you must also be attentive to protect other fishes from the new ones.

It is because it might be a carrier of other diseases or parasites that can affect the survival of the other species in the same tank or aquarium. The two methods mentioned above are the easiest ways to acclimate fish that every fish owner must know.

It is to let the new fish live longer after purchasing or transferring it from one to another water environment.