Yes and no!
Consider these points when you decide whether or not you need a betta fish filter.
I have a half-moon betta with very long fins? You may want to set up a betta fish tank without a filter. Or, maybe use a Sponge filter for betta tank which are great for small aquariums. A sponge filter will keep water movement to a minimum if tearing fins is a concern.
My betta is kept in a community tank with many fish? Simply put, more fish = more waste = more toxins. A filter would be recommended in this situation. Also, a community tank is likely to be a little larger providing your betta hiding places to escape water currents.
How many water changes are you willing to complete, weekly or twice a week? If you can’t dedicate the time to change your water more than once a week a filter would be the way to go.
My aquarium has many live plants? In this situation, live plants actually act as a natural filter and can provide oxygen, filtration, food and a place to hide.
Tank size larger than 2.5 Gallons: For this size, a filter would be the way to go. Just ensure the filter has an adjustable flow rate to control the amount of current.
Another option is to select a filter down a level rated for a smaller aquarium.
Tank size smaller than 2.5 Gallons: First of all never keep your betta in anything smaller than 2.5 gallons. In small aquariums the water can foul much faster than larger aquariums, requiring more regular maintenance and water changes. Foul water can lead to multiple issues such as health, disease and even death.
However, if you must keep your betta in something less than 2.5 gallons, we would recommend a sponge filter. To ensure the currents don’t become too strong and cause harm to your betta.
For tanks smaller than 2.5 gallons we suggest you maintain a clean tank through regular water changes. However, there are filters that can accommodate tanks of this size.
Do betta fish need a filter in their tank?
All aquariums require clean water and filters are a great way to maintain clean water free from contaminants and allow the build-up of healthy bacteria that are beneficial to your fish.
If you want healthy a Betta fish the water should be kept clean and clear.
When deciding to have a Betta fish filter or no filter at all. Your situation should determine whether or not you need one.