Do Betta Fish need a Filter?

The truth is, there is no straight answer to the question since betta fish can survive and maybe thrive in either scenario, given the right care that you would give.

Whether your betta fish require a filter or not would actually depend on various factors, including the size of your tank size, the kind of care you give to the fish, tank mates, among others.

Some Thoughts to Consider

Caretakers, especially those just beginners, may think it is good to get a bowl or a small tank for their fish since it is affordable. However, this is not true, and you might end up taking care of a sick betta, or worse.

What does this mean? This means before you actually consider buying a filter or not, you really have first to evaluate the advantages and disadvantages of your decision.

Let us start with the natural habitat of a betta fish, which lives in shallow bodies of water, including rice paddies.

The Power of Evolution

During droughts or hot summers, a wild betta can still live with just a little oxygen in a murky puddle for a good period of time. This is because betta fish can evolve, using their ability to get oxygen from the air, which is at the water’s surface. Other fish solely rely on their gills to get oxygen. But not betta fish, which is classified as labyrinth fish, have a labyrinth organ that enables them to breathe air.

Because of their capacity to survive in low oxygenated water, betta fish are recommended for newbie fish caretakers. In fact, many beginners also seek fish, which can be easier to care for than other tropical fish and with less equipment.

Betta Fish Habitats that have Filters

Tanks that are 2.5 gallons and below should not be using a filter because they may end up doing more harm than good. In small tanks, filters may cause strong currents, possibly tossing your fish around and stressing them out.

Bettas are considered not very strong swimmers. In addition, their long fins may further complicate their mobility, especially during currents. Betta fish prefer still water, or at the very least, slow-moving. That way, their natural ecosystem gets replicated. This is one major reason why some people, especially veteran caretakers, recommend unfiltered tanks for betta owners.

The problem with low-volume tanks that are unfiltered is water quality declines quickly. When you have a bigger volume, there is a higher chance water quality will not decline that easily. It is also easier to maintain.

You also have to look for uneaten food and feces as they may result in nitrate, ammonia, and nitrites building up. When they are already in high quantities in your tank’s water, they can make your betta really sick.

In small and unfiltered tanks, another problem is fin and tail rot. That is one of the most frequent ailments in such tanks.

However, you also have to check out against changing the water constantly. Frequent water changes can affect the growth of beneficial microorganisms naturally existing in the water and may stress your betta fish.

Consider 2.5 gallons as your minimum size for your betta fish. The recommended size is 5 gallons or even more. Taking care of your betta fish in an unfiltered tank at 2.5 gallons can actually give you a lot of work.

Unfiltered tanks need between one and two water cycles at around 25 percent weekly. You have to change the water 100 percent per week. But of course, this would also depend on the quality of the tank’s water.

A five-gallon tank with no filter only needs one water cycle per week between 25 and 30 percent of the tank water’s total volume. Once a month, you need to change the water 100 percent.

To check the quality of your water on a real-time basis, you should use test strips.

You should also use test strips to analyze your water parameters in real-time. You can remove the visible uneaten food and poop before using the strips.

Betta Fish with filtered Tanks

Some caretakers prefer putting their betta fish in filtered tanks.

Filtered tanks can help maintain the beneficial bacteria existing naturally in the water while neutralizing ammonia and nitrates. Having a natural ecosystem for betta fish is important to their long-term health and reduces the possibilities of stress and disease.

If your tank does not come with a filter, you can buy it separately. There are a lot of filters out there: Sponge filters, under gravel filters, internal filters, among others. The top consideration when buying a filter is the strength of your betta fish. You should look for a filter that can adjust its flow. Your fish should be able to swim without worrying or struggling freely.

Filtered tanks for your betta fish will also require less maintenance, making life for you easier. You do not need to change the water completely in a filtered tank unless you have an algae issue or a rampant disease problem. You only need to change 25-30 percent of the water’s volume once a week.

Aside from water, you just need to vacuum the gravel, change the filter from time to time, among others. Make sure you always clean the filter in tank water. Do not use tap water, so you preserve the tank water’s beneficial bacteria.

Is the Filter too strong for your Betta?

If the tank’s filter is too strong for your betta fish, you have to remove it or at least adjust the current’s strength. Do not use a filter if your tank is under three gallons.

If your betta fish is really struggling to go to the surface to breathe air, frantically swimming in your tank, hiding, and looking really scared, your filter might be probably too strong for them.

If you have a filter that is too strong, it can substantially stress your betta fish and result in fin damage, injuries, or worse, death. When the filter causes a strong current, your betta fish might become physically exhausted. When this happens, the cab is quickly tossed around or sucked up by the intake tube of your filter.

Check if your filter can adjust its settings. If it has, then tries putting it in the lowest setting. If your filter cannot adjust its settings, consider returning it or buy a new one. You can also follow some of these tips:

  1. Try increasing the plants or decorations that you have near the filter to break the current flow.
  2. Create a separate compartment for your filtration needs by dividing your tank.
  3. Use a pre-filter sponge to restrict your tank’s water uptake and reduce the current flow.

Conclusion – Do Betta Fish need a Filter?

Do your betta fish really need a filter? Again, that depends on your personal situation and preference, as well as your decision given the advantages and disadvantages of using a filter.

In small tanks, filters may trigger strong currents in your tank water, possibly exhausting your betta fish and stressing them out. An unfiltered one also mimics the natural habitat of your betta fish.

A filtered tank, on the other hand, can also support a healthy ecosystem for your betta fish. A filtered tank can also increase oxygenation in the water, boost water quality, and reduce your maintenance work.

But either you pick an unfiltered tank or a filtered one, please avoid using tanks or fish bowls that are under 2.5 gallons. The bigger your tank, the faster it will be for you to maintain it.

Before You Go

In case you are wondering: How do I add betta fish in my aquarium?

It is actually fairly easy. After you buy your betta fish, bring it home right away.

Next, place the betta fish in the aquarium or tank – still inside the bag. Do this process for about 15 minutes so that your fish can get used to the tank’s new water temperature.

Afterward, you can use a net to transfer the fish into the aquarium or water tank. Do not add any water from the bag you used to buy the fish to your aquarium.

You must add only one betta to the aquarium. You can have more than one betta fishes if the tank is divided and each betta has its own section. If your pets see each other for a long period of time, they can get stressed.

You can have dividers with solid colors so that your pets would have completely separate areas and the water is not shared. If you use dividers with solid colors, your betta fish cannot see through. You can also make your tank heavily planted to provide a secure environment for the fish.

The chemical balance in the aquarium transforms every time you introduce new fish, so you have to regularly check the water’s ammonia, pH, nitrate, and nitrite levels.

A detailed Care Guide to the Betta Fish can be found here:

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