introduce a fish to a tank
How to Introduce Fish to a New Tank

Many of us before have come home from the pet store, from which a beautiful new pet beta fish was purchased. Out of pure excitement, the little guy was thrown into a new tank almost immediately. The fish seemed fine at first, but just a few hours later, it had sunken to the bottom of the floor—lifeless. Quit killing your fish, it’s time to become a careful and informed fish owner once and for all. With sudden changes in water temperature, aquarium size and pH levels in need of consideration, here’s a simple “how-to” for introducing fish to a new tank.

Consider Size

When prepping an aquarium for your new friend to be introduced into, the size of the tank/aquarium is important to consider. Often, new fish owners will put their pet fish into restricting, small tanks that shouldn’t even exist. If a fish does not have much room, it will stress out too much and eventually die. Do research on your fish’s species so that you get a tank large enough to allow it to grow and thrive happily.

Chemical and pH Level Check

Tap water is saturated by ammonia and chlorine, so much so that it can easily kill your fish. For this reason, prep your water with de-chlorinator and ammonia binder treatments, both of which are sold here at Allan’s Pet Center. Keeping these levels in check will help you balance the overall pH for your fish to live healthily in. If the pH is drastically off compared to the pH levels inside of the bag your fish came in, then you have to further treat the water.

Water Temperature

Adjusting the water temperature within your fish’s new tank is also important when introducing fish to a new tank. However, doing this is much easier than adjusting chemical levels. Simply adjust the water to the same temperature as the water in the bag that you brought your fish home in. You do this by placing the sealed bag (with fish inside the bag) into the tank so that the water temperature in the bag equalizes with the aquarium’s temperature.


pet shop, pet fish, betta fishIntroducing Your Fish

Here is the most dangerous part—the moment we’ve been waiting for—introducing your fish to a new tank. However, first, make sure any lights surrounding or placed within the tank are switched off. Once that has been taken care of, open the bag and carefully swap water between the bag and aquarium so that the fish slowly adjusts to its surroundings.

According to The Spruce, you should repeat the same process as many times as needed to balance the pH of the bag water, based on the initial pH difference: pH difference of 0.1 and 0.3: Add 1/2 cup of tank water every 15 minutes for 1 hour, or until the pH is equal. pH difference of 0.4 or more: Add 1/2 cup of tank water every 15 minutes for 2 hours, or until the pH is equal to the aquarium water pH.  Once this is done, quickly but gently lift your fish out of its bag with a small net and place it into its new tank.

Now, allow your fish to acclimate and keep any lights turned off for a few hours. Remember slow acclimation is a must when you introduce fish to a new tank.

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