How to Transfer Betta Fish from Cup To Tank

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Introducing your new Betta to their aquarium is not as easy as simply opening their cup and plopping them in.

You need to know how to transfer Betta fish from cup to tank.

There are specific steps to take that will ensure your fish is safely acclimated to his new home. 

This will avoid any unnecessary stress on your fish and give them the best start possible. 

Bringing Home a Betta Fish

Make sure your tank is already set up and cycled before you go to buy your Betta fish.

Your fish tank needs time to build up good bacteria that will combat the ammonia produced by your fish.

Before you go to pick up your Betta, prepare a travel bag or box for the trip.

Line it with towels or newspaper to ensure the container does not bounce around on your way home.

The darkness of this space will help calm your fish and reduce stress on the journey.

It is very important to go straight home from the pet store/breeder.

Do not leave your fish in a hot car while running errands.

This can increase the temperature in their bag and worst case scenario, your fish could die.

Now onto acclimating.

Acclimate a Betta Fish

Acclimation is the process where we move our fish from its container/bag into the aquarium.

This is important for a number of reasons.

Many levels in the water will change when shipping, such as the ammonia levels and Ph.

The temperature will also be affected.

Acclimating your fish will gradually adjust the temperature in the bag to your current tank temperature and introduce your fish to the different ammonia and Ph levels in your tank.

Transferring betta fish

First Steps After Arriving Home

Firstly, turn your aquarium lights off.

As mentioned before, darkness means a less stressed Betta and your lights can increase the temperature of a fish sitting near the surface. 

To safely acclimate your fish there are two options. Drip acclimating or water swopping.

I personally use the water swap method most often, especially when dealing with fish like bettas. It is simple and effective but you can decide what option you prefer.

The Water Swapping Method

If your Betta has traveled in a cup you will need to move him and his water into a clear plastic bag for the acclimation process.

Once you have moved your Betta into the bag, knot the top or secure it with an elastic band to create an air bubble.

This will ensure your bagged fish will float.

Place the bag into your fish tank and it should float on the surface of the water.

Leave your fish floating in the closed bag for 20 minutes, this will slowly adjust the water in the bag to the temperature of the water in your tank.

Do not leave them floating for much longer than this. 

You are ideally wanting to get your fish into the tank as soon as possible.

Once your fish has floated for 20 minutes, you can start the water swapping method.

Open the bag as gently as possible and use a peg to attach it to the side of the tank to avoid it sinking. 

Get a small sterile cup and take a cup of the fish tank’s water and pour it slowly into the bag containing your Betta.

Repeat this step every 15 minutes or so for roughly an hour. I like to aim for about 5 exchanges.

When completed, use a net to gently move your Betta into the tank.

Avoid pouring the rest of the container water in with the fish, you have no idea what diseases could come in the water from the pet store

Drip Acclimating Your Betta

The drip method is the go-to technique for most modern home aquarists.

Not only does it allow your fish to acclimate to your tank’s temperature, but it also helps them adjust to other parameters like pH levels, hardness, etc.

It’s pretty easy to do. The following discussion will take you through the drip method, step-by-step:

 Materials that you will need:

  • A plastic bucket (2 gallons)
  • Airline tubing

Method step by step:

  • Pour the fish and the water gently into a bucket or container. You’ll want to make sure that the fish is fully submerged.
  • Stick an air stone in the bucket and pump some air into it.
  • Put the bucket on the floor next to the aquarium you’ll be putting the fish into after it’s finished being acclimated.
  • Use a piece of plastic air line and an air valve to create a siphon line from the aquarium to your fish’s bucket.
  • Turn on the siphon and let the water trickle into the bucket. You want to aim for about 5 drips a second.
  • Once the water level has doubled, remove half of the water in the bucket and resume the drip method until the water has again doubled. This process will take between 30 minutes to an hour.
  • Remove your fish from the bucket using a net and place it into your tank. Do not use any of the water in the bucket.
  • Top up the tank using dechlorinated water.

It doesn’t matter what type of acclimation you use, keeping an eye on your Betta fish is crucial.

It’s possible for a new fish to go into shock after a cup-to-tank transition goes awry.

At the very least, keep an eye on newly transferred Bettas for a week.

Signs of distress include clamped fins, a dulled colour, a lack of interest in food, and a tendency to hide.

Keep in mind that each Betta is unique, and some may be better at coping with a transfer than others.

Betta in Community tank

Introducing a Betta to a Community Tank

Betta males cannot ever be kept with another male.

They will fight each other to the death.

Female Bettas can be kept in a sorority tank provided it is big enough, but I would not recommend doing this for beginner fish keepers. 

If you would like to keep your Betta in a community tank, there are many good options.

I personally have had great success with keeping my male with a school of rummy-nose tetras and 4 cory catfish. 

You want to avoid keeping your Betta with fish that are known ‘tail-nippers’ such as tiger barbs, loaches and cichlids.

When adding your fish to a community tank, it is often advised to feed your other fish at the same time so that they are distracted by the food and not interested in the new Betta. 

Once you have added your Betta to your community tank, keep a close eye on things for the next few days.

It is important to have a back up plan (a second tank) because it is hard to predict exactly how everyone will get on. 

Out of the 6 Bettas I have owned, I only had problems with one male not accepting tank mates.

It will be obvious after a few days if your fish are not getting on.

If you have spotted any of your fish with injuries such as scrapes on their sides or damaged fins, this is a sign of things not working.

It is natural for fish to sometimes swim after each other, as long as it ends there and the fish being swam after doesn’t show any signs of fear such as hiding in the corner or being afraid to eat at meal time.

Signs of Illness or Injury

Keep a look out for any signs of an unhappy Betta in the few weeks after adding it to the tank.

Illness symptoms could present as a loss of appetite, abdominal swelling, fins clamped tightly to their sides or discoloration of the skin or fins.

This could also be a sign of poor water quality or unbalanced water levels.

Make sure to use a water test kit to ensure your water is not the problem. 


Remember, good acclamation takes patience.

Do not rush the process and keep stress to a minimum.

If you follow these steps, you will give your Betta the best chance to thrive in his new environment.

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Irma Bense is the founder of She has over 42 years of experience in keeping fish.She has kept both freshwater and saltwater fish through the years.She has extensive knowledge in breeding numerous species of fish from Show Guppies, Cory Catfish, German Blue Rams to Apistogrammas.You can learn more about Irma on the 'About' page.

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