Since betta fish breathe air directly from the top of the water, your tank does not need a filtration system. In fact, it’s better if the tank doesn’t have one—the current created by the filtration is stressful to bettas. [2] X Research source
The tank does not necessarily have to be a traditional fish tank; any large container will do. It’s important that you include gravel in the fish tank. Opt for a neutral color, and for relatively small-grained gravel. The neutral color will calm your betta, and bacteria that build up on the gravel will digest your fish’s waste and keep the water relatively clean. [3] X Research source
For this reason, a narrow-topped container like a wine bottle does not make a suitable tank for a betta.
If you bought your betta at a pet store, you should have received a water conditioner specifically made for bettas. If you were not given one, you’ll need to purchase a conditioner on your own. [6] X Research source Conditioners should be available at any pet store, and can also be easily purchased online. The amount of conditioner that you use will vary based on the size of your fish tank. Follow the directions on the bottle regarding the amount of conditioner to use, and the amount of time to let it mix in the water before it’s safe for your fish. [7] X Research source If you live in a rural area where the tap water is not chlorinated, you may not need to use a conditioner. Some conditioners get rid of heavy metals though, so you can use it if you need.
This process is known as “floating” the betta. Let the bag sit in the tank for 15-30 minutes. [8] X Expert Source Craig MortonFish & Aquarium Specialist Expert Interview. 21 July 2020.
You’ll need to stand there and hold the bag upright during this time. If you release the bag or let it tilt too far to one side or the other, the water will spill out into the tank.
Repeat the step one more time: mix another cup of tank water into the bag with the betta. Continue to hold the bag in the tank during this time. Make sure to keep the cut in the bag facing upright.
Avoid adding the water from the bag to the tank. [9] X Expert Source Craig MortonFish & Aquarium Specialist Expert Interview. 21 July 2020. After the fish has been acclimated, you can also take an aquarium net and gently place your betta in the tank. Do not feed your betta right away. The fish will probably not eat for the first day it’s in a new tank. Some bettas will refuse to eat for the first three days, sometimes even a week.
Let the cup float for about 15 minutes.
The betta needs to get used to some of the tank water, as it will have a different mineral hardness and pH level, in addition to a different temperature. Leave this to sit for 15 minutes.
At this point, you can use your fingers to feel the temperature of the fish-tank water and the cup water. They should be roughly the same temperature.
If the water in the betta’s cup is relatively clean of excrement and silt, you can pour the fish and its water directly into the tank.
