How to Properly Acclimate New Fish in the Aquarium

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When you are stocking your aquarium for the first time, you may want to take the time to think about the order in which you add your fish – especially if you are cultivating multiple species. Some fish are more aggressive than others, so you might need to add them to the tank first so they can establish their territory. Not only do you need to think about the order in which you add fish to your tank, however – you also need to think about HOW you add them to the tank. Proper acclimation is essential for the health and safety of your aquarium fish.

Why Do You Have to Acclimate Fish Slowly?

Many novice aquarium hobbyists make the mistake of bringing their fish home from the pet store and simply emptying the bag into their tank. Then, they are surprised when their new fish die after just a few hours in the new tank. What these hobbyists do not realize is that the conditions in the pet store tanks could be different from the conditions in their tank at home. By throwing the fish into a new environment all at once, they are shocking the fish and causing them to become stressed and die. Acclimating new fish slowly helps the fish get used to differences in water temperature and water conditions before they are released into the tank. If you want to make sure that your new fish do not die right away, you need to learn how to acclimate them properly.

Methods for Acclimation

There are several different methods that aquarium hobbyists use to acclimate new fish to their tanks. The three most common methods are the floating bag method, the bucket method, and the drip method. The floating bag method is just what it sounds like – you take the bag that you brought your new fish home in and float it in the tank in order to give your fish time to acclimate to the temperature in your tank. You will also need to add small amounts of tank water to the bag over a period of time to get your fish used to any differences in water chemistry. The bucket method involves placing your fish (along with the water from the bag) in a bucket to which you add small amounts of tank water over a period of time. The drip method is by far the slowest method for acclimation, but that is also what makes it the best choice in many cases.

The Drip Method of Acclimation

To utilize the drip method of acclimation for your new fish, you should still start out by floating the bag containing your fish in the tank for at least 15 minutes – this will help to make sure that the temperature in the bag evens out to match the temperature in your tank. After the temperature acclimation period you can empty the bag into a clean bucket to begin drip acclimation. Start by tying a few loose knots in a length of aquarium airline tubing then place one end of the tubing into the aquarium and use a clip to hold it in place. Next, create a siphon by sucking on the other end of the tube until the water starts to flow through it. Then, position the end of the tubing over the bucket and hold it in place with a clip.

Start out the acclimation process with the water flowing through the tube at a rate of 2 to 4 drips per second. You can adjust the flow rate by tightening or loosening the knots in the airline tubing. Wait until the water volume in the bucket doubles, then discard half of it and start the process again. Once the volume of water in the bucket doubles again it is safe to say that your fish have been acclimated properly. At this point you can use a mesh net to catch the fish and then transfer them to the tank.

The process of acclimating new fish to the conditions in your aquarium can be a time-consuming process but it is necessary. If you rush the process you might end up putting the new fish in your tank before they are used to the new tank conditions and, as a result, they could become stressed and die. Do yourself and your fish a favor by acclimating your fish properly.