5 Tips for Introducing New Fish to Your Aquarium

Written and verified by the lawyer Francisco María García

Last update: 27 December, 2022

An aquarium can be a really elegant decorative element, and is thought to be a great way to combat stress. Plus, it’s a good way to teach children about the responsibilities of looking after a pet from a young age. Today we’ll tell you all about introducing new fish to your tank.

5 tips for safely introducing new fish into your aquarium

In this article, we’ll give you some practical pieces of advice to help you to safely set up your aquarium:

Setting up the tank

Your eagerness to see your new fish swimming around the aquarium shouldn’t outweigh the time you spend setting it up.

The first thing you need to do is to work out where you’re going to place your aquarium. You need a flat, stable surface with good lighting, ideally somewhere far away from any strong air currents.

The size of your aquarium will determine which filter you need to keep your tank clean. Decorative items such as sand and plants can really help bring your tank to life. While you might think this is merely a question of aesthetics, they’re actually really useful for creating a more natural environment for your fish to hide and swim around in. You need to place them where they won’t get in the way, and make sure they don’t take up too much room.

Water straight from the faucet should be the right temperature for filling your aquarium. You then need to add dechlorinator and other water conditioners to maintain the right chemical balance for your fish.

Before introducing new fish to your aquarium you need to leave it to cycle for around two weeks. This will guarantee a safe environment for your new family members.

Choosing the right fish

Not all species get on well together. It’s important to do your research on which species you can keep in the same tank before you go out to buy your fish. Integrating new fish can take time, but the simplest way to do it is to introduce them in pairs. Adding a new pair every week will make it easier for them to adapt to life in their new home.

With all the excitement of buying new fish, it’s important not to forget to pay attention to the type of water they need. Fish can be either freshwater or saltwater. The latter often take longer to acclimatize, and maintaining the salt levels can be hard work.

 Stress-free transportation

At the pet store, your new fish will be placed in a transparent bag for you to take them home in. We’d recommend putting the bag inside a box, so that the change of lighting doesn’t cause your fish unnecessary stress. As comfortable and as short a journey as possible will reduce any additional risks to your pets.

If you’re combining getting your new fish with a little shopping trip, it’s best to pick up your pets just before you head home. It’s important to remember that spending hours inside a small bag isn’t particularly comfortable for your fish, so it’s best to keep it to a minimum.

Introducing new fish

When it comes to introducing the first few fish into your tank, you can acclimatize them by getting the right temperature for them. Don’t simply open the bag right away and pour your fish straight out into their new home; the shock of the change in temperature can actually be enough to kill them. The idea is to let the temperature of the water in the bag gradually adjust itself to match the temperature in the rest of tank.

Leaving the bag closed, gently place it in the water. After about fifteen minutes, you can pour a small cup of water from the aquarium into the bag. Wait ten more minutes, then use a net to scoop out your fish and release them into their new home. Don’t pour all the water from the bag into the aquarium, as it may be contaminated.

The process is similar if there are already fish living in your tank. The main difference is that you need to turn out the light before you introduce your new fish into the aquarium. That way, the other fish won’t be as focused on the new arrivals, and they can get used to each other in a slower and more natural way.

Feeding your fish

When you feed your fish will depend on whether they are the first fish to be introduced to that tank, or whether you are adding fish to a pre-established community. If they are the first fish in the tank, you can wait 24 hours before you feed them. If there are already fish in the tank, you can simply feed them at the same time you normally would.

Introducing new fish to your aquarium is really simple, but it does have its risks. By following these simple pieces of advice, you’ll be able to avoid stress and potentially losing some of your fish, which is especially important if you’ve just spent a lot of money on them.