Despite what you may have heard, bubbles in a betta fish tank are an optional, rather than mandatory, feature.
While bubbles produced by an air pump can increase the amount of dissolved oxygen in the water, there are other perfectly good ways to oxygenate your fish tank.
But do bettas like bubbles?The answer is that some do and some don’t, and it depends on the type of bubbles.
Curious to learn more? Let’s dive in to learn all about bettas and bubbles.
How Are Air Bubbles Created in An Aquarium?
Bubbles are delivered to an aquarium by an external air pump via an air hose. The air pump pushes air from outside of the tank into the airline, which runs down to the bottom of the aquarium to release bubbles into the tank water.
The air hose can be simply tucked into the gravel to release large bubbles, or it is more commonly connected to a sponge filter or bubbler.
What’s a Sponge Filter?
Sponge filters are some of the simplest and cheapest aquarium filters, and their gentle nature makes them especially good for betta tanks.
Typically powered exclusively by an air pump, they use the current created by the bubbles to push water through a sponge that filters the water. Bubbles are then released through the top of the sponge filter to rise to the water’s surface.
Some sponge filters come with an internal airstone to improve aeration.
What’s an Airstone?
An airstone (also known as a bubble stone) is a device attached to the output of the air hose to diffuse the large bubbles from the air pump into a cloud of tiny bubbles.
This improves oxygenation in the water by increasing the surface area of the bubbles and also makes the movement of bubbles slower and more gentle.
Other Types of Bubblers
An air pump can also be attached to a bubble wall, bar, or wand. These long tubes are good at releasing bubbles over an extended area but often don’t make bubbles quite as fine as an airstone.
What’s the Best Type of Bubbler for Betta Fish?
Since betta fish prefer a gentle flow of slow-moving water, bubblers that produce very fine bubbles are the best option. Airstones are typically better at this than bubble walls or bars, but there are still many types of air stones to choose from.
Limewood air stones are some of the best for producing a fizz of very fine bubbles that are less likely to cause disturbance to your betta fish.
How To Install an Airstone
Installing an airstone into your tank to produce bubbles is simple.
Connect your airstone to your air pump with a 3/16-inch airline hose, and secure your airstone at the bottom of the aquarium.
If your air pump has a check valve, you can place it anywhere around your fish tank. If it doesn’t, you’ll need to keep your air pump above your tank to prevent water from running back into it, which would likely destroy it.
Do Betta Fish Need Oxygen?
Yes! Betta fish, like every other fish species, need oxygen to survive. Without it, they’ll die in a matter of minutes.
What separates betta fish from most other fish is that they’re equipped with a special physiological adaptation known as a labyrinth organ that enables them to breathe oxygen from the air and extract it from water.
Bettas have evolved this remarkable ability due to living in shallow, stagnant waters like rice paddies that can become very low in oxygen.
Despite this, bettas and other labyrinth fish must also have some oxygen dissolved in the water. They prefer breathing some oxygen in the water via their gills and some through their mouth at the water’s surface. This means there needs to be adequate levels of oxygen dissolved in their water.
Do Betta Fish Need an Air Pump?
Although betta fish need some oxygen dissolved in the water, they don’t necessarily require an air pump to produce bubbles.
A certain amount of oxygen is always being dissolved at the water’s surface. This gas exchange process is increased if the water’s surface is agitated by water movement.
Air pumps increase the gas exchange at the water’s surface by agitating the water, but other types of filters can also perform the same job. Internal power filters or hang-on-back (HOB) filters also push water around the tank to create a current. If the filter output is above the water’s surface, the mini waterfall effect will also create bubbles and help oxygenate the water.
The trouble is that betta fish don’t tend to enjoy fast currents or water disturbance, meaning power filters may be inappropriate, especially in smaller tanks. Sponge filters powered by an air pump can be a better choice in many circumstances.
Do Betta Fish Enjoy Bubbles?
There is mixed opinion about how much betta fish enjoy bubbles. Ultimately it comes down to the types of bubbles created and the preferences of your particular betta fish.
For a betta fish to enjoy bubbles, you definitely need a good air stone. If your air hose just releases air directly to the aquarium without an air stone, the bubbles will be huge spheres rocketing to the top of the tank. A delicate betta fish won’t be able to enjoy these kinds of bubbles and may even become frightened and stressed by them.
On the other hand, an airstone that releases a fizz of tiny, gentle bubbles will seem much more benevolent to your betta. They may even learn to enjoy interacting with them!
Do Bettas Like to Play With Bubbles?
While some bettas will avoid making direct contact with bubbles, others will positively seek them out. This depends a lot on your betta’s temperament. Just like us, every betta fish has a unique character. While some humans enjoy wild adrenaline rushes, others prefer calmer activities for stimulation.
If your betta is daring and playful by nature, he may enjoy frolicking in the stream of bubbles and spend lots of time right above the airstone. If you’ve ever been in a jacuzzi, you’ll know just how pleasant bubbles moving over your skin can feel, and maybe it’s the same for your pet fish!
But for other bettas, bubbles are not their idea of fun at all. Long-finned varieties, in particular, may find it especially hard to battle against a powerful current caused by an air pump and may even find bubbles quite stressful.
Can Bubbles Hurt My Betta?
If your fish is caught in a fast-flowing stream of bubbles, he may temporarily lose command of his movement and be driven up toward the water’s surface. Once at the surface, though, the current will disperse and move your betta horizontally away from the bubbler. Therefore, it’s doubtful that the bubbles would cause your betta any lasting damage.
However, a bubbling stream that is too powerful may cause a current in the tank that’s stressful for your fish. Betta fish are from relatively still or slow-moving waters and are not adapted to cope with fast currents.
A betta feeling constantly stressed by a fast bubble stream may be more prone to ailments and diseases, so it’s important to find an air pump that’s not too powerful.
How Powerful Should My Air Pump Be for a Betta Fish?
Your air pump’s electrical charge, or wattage, will largely determine the rate at which bubbles are produced and the strength of current created by them. Being delicate fish, bettas prefer the water current to be on the gentle side.
A 2-2.5 watt air pump would be appropriate for tanks up to 20 gallons in size. For a 40-gallon aquarium, a 3-watt pump should produce about the right current.
You want to strike the right balance between an air pump or filter that provides the tank with enough oxygen while not causing too much disturbance to your betta.
How Do I Tell if My Aquarium Is Low in Oxygen?
A healthy aquarium should have 80-110% oxygen saturation and a DO (dissolved oxygen) level of 6-8 mg/L.
If oxygen levels fall below these levels, your fish will begin to show symptoms of oxygen depletion (also known as hypoxia). Fish lacking in oxygen will breathe faster and show more rapid gill movement. They will also become more lethargic and less interested in food.
While bettas, gouramis, and many catfish naturally inhale a portion of their oxygen from the water’s surface, in most other fish, surface breathing indicates dangerously low oxygen levels. This is the last resort for many species since the surface is the most vulnerable place for a fish.
If you notice any of these symptoms in your fish, you need to act fast. While bettas are more tolerant of low oxygen levels than most fish, oxygen depletion can still cause significant damage to fish health.
Oxygenating Your Aquarium in an Emergency
Test your water for dissolved oxygen using a DO test kit. If levels are too low, the fastest way to rectify the situation is to do a partial water change with well-oxygenated water.
Quick breathing at the water surface is an unmistakable sign for an oxygen deficiency. Unfortunately, it may then already be too late for acting appropriately.
If low oxygen levels have been caused by very hot weather overheating your tank, then partial water changes or ice cubes can help to lower the temperature back down to a safe level.
However, note that temperature changes must always be made very carefully and gradually to avoid thermal shock to your fish.
Keeping Your Aquarium Well-Oxygenated
As we’ve said, bubbles aren’t the only way to oxygenate a fish tank. Any type of filter that agitates the water’s surface sufficiently will help atmospheric oxygen to dissolve into the water.
Along with a good filter, regular partial water changes and keeping the tank clean will help maintain healthy dissolved oxygen levels. Clean water contains fewer bacteria that would otherwise consume some of the oxygen available to your fish.
Live plants are another great way of increasing oxygen levels. Like terrestrial plants, aquatic plants absorb carbon dioxide and expel oxygen, producing extra oxygen in the water through photosynthesis.
What Are Betta Bubble Nests?
When a male betta splendens reaches reproductive maturity, you may see him collecting bubbles at the water’s surface to build a nest. This is typical breeding behavior and a good sign that you have a happy and healthy male betta.
Even if you don’t have a female around, a male betta will still build a nest, hoping to impress the gorgeous betta girl that he dreams might swim his way tomorrow.
The bubbles created by an air pump have nothing to do with this behavior, although, as a side note, a sponge filter powered by a gentle air pump is a good choice for bettas during breeding time, as it creates little current and won’t disturb their bubble nest.
When bubbles are delivered by a gentle air pump and dispersed by a good airstone, many bettas will enjoy the presence of bubbles in their aquarium.
Even if some individuals don’t like to play in the stream of bubbles, your pet betta fish may benefit from the additional oxygen an air pump produces.
If you don’t want bubbles in your tank, there are plenty of other ways to oxygenate your water. Along with maintaining good water quality, any filter that agitates the water’s surface should ensure you have enough oxygen in the water to keep your betta healthy and happy.