Ever noticed those little collections of bubbles at the top of your betta fish tank? Ever wondered what they are, why the bettas make bubble nests on the surface of the water, and what the heck they do? Why don’t they disappear?
Well, that’s what I’m going to tell you today.
These little collections of bubbles are known as bubble nests. They’re a normal, healthy part of your betta fish’s life – and they’re kind of wonderful.
Let’s take a look.
What is a Bubble Nest?
A bubble nest, sometimes called a foam nest, is a type of nest created by certain types of fish and frog species. It is a floating mass of bubbles that is created by a mix of saliva bubbles, oral secretions, and sometimes aquatic plants.
The nests are intended to be a place for the fertilized eggs to be placed in while incubating before the little baby bettas pop out and grow into more beautiful freshwater beauties.
Author Note: Normally one or both parents will guard the nest until the fry hatch. In cases where only a single parent stays to guard, it tends to be the male.
The species of fish that create and guard bubble nests are known as aphrophils.
Species that make bubbles nests include gouramis, Momoppterus alba, Hepsetus odoe, and the electric eel. And, of course, betta splendens.
Most, but not all, of the fish which love building bubble nests live in waters that are tropical, standing, and depleted of oxygen.
What is the Betta Bubble Nest For?
Male Betta fish will first complete a bubble nest before they seek out a mate and start spawning. Once the fish is ready it will both start to drive away any rival fish and start to court a mate.
When keeping Betta fish in captivity, if you place a female fish alongside a male it will cause him to start working overtime in order to get a nest ready because of knowing he is in the presence of a female that is ready for a mate.
After the male is able to impress the female, they will mate. After the fertilized eggs are ready, the male will pick up the eggs by mouth and place them in the nest.
Top Tip: It takes around two to three days for the fish to hatch. The young fry are terrible swimmers when they are firstborn. The bubble nest acts to keep the fry safe until they are capable of swimming.
Frequently the nests will contain weeds and debris in order to give sufficient dividers to keep the fish safe from the rest of the world.
Why Do Bettas Build Bubble Nests?
Betta fish, sometimes called Siamese fighting fish, tend to occupy shallow waters that have little oxygen. The bubble part of the bubble nest acts to give oxygen-rich air for the eggs and newly hatched fry.
The nest can pull double duty in protecting and giving a healthy environment for the young fry.
When constructing the nest the betta gulp air at the surface and then blow saliva bubbles. (So, though we tell the kids not to do that, it’s actually a good sign in male bettas!) The bubbles are then placed under leaves or other floating objects for protection.
In the Wild
Male Betta fish have no issue when it comes to trying to attract a mate. The Betta is known for having beautiful colorings, majestic tails, and they are truly architects when it comes to creating the perfect bubble nest.
While betta fish build the nest it’s typically a major step in courting the male Betta does solo as an attempt at catching the interest of a nearby female.
She’ll know how resourceful the male is being and offer a fin of support and decide to make some adorable baby betta fish with him to fill that intrepid nest.
In Your Home
Male Betta fish are known for beginning construction on a bubble nest if their environment has an unexpected change. These changes can include a quick rise or fall in barometric pressure or water temperature.
Top Tip: Another change that can trigger this is if you take away or change out the substrate or accessories of the aquarium or during significant water changes.
In the wild, Betta fish can be triggered to start nest construction with something as simple as a change in rainfall patterns or an elevation or decline in temperature, even a few degrees Fahrenheit.
What Does the Labyrinth Organ Have to Do With It?
Betta fish have a labyrinth organ and this allows them to breathe air on the surface of the water. The Betta fish tank must have enough room for the fish to surface and gulp air as needed.
The fish will breathe in oxygen in regular air. This supplements the air that they can get by processing the water through their gills.
The labyrinth organ functions by air being forced inside of it. The organ itself is a maze of numerous maze-like compartments that are made of the lamella (thus the name of the organ).
Lamella is a membrane that is covered by an incredibly small boney plate. The oxygen passes through the lamella membrane and this causes the oxygen to be absorbed into the body.
The Building of the Nest
Male Bettas will utilize their labyrinth in the construction of nests. After taking a deep breath of air, the fish will swim down to the location it will build its nest.
A combination of bubbles along with the fish’s saliva makes up the basic structure of the bubble nest.
The saliva is used to coat the bubbles to prevent them from popping during construction and ensure the nest lasts long enough for the fry to hatch.
Generally fish do not want to the address stress of humans watching, but some bettas do not mind. The nest-building itself is a very frantic affair that is loud.
How Often Do Bettas Build Bubble Nests?
Each Betta fish is unique and has its own personality, so the frequency of a healthy betta‘s nest-building habits rests on their mood, temperament, and desire to court a mate.
Some Bettas with build bubble nests frequently, some only on a rare occasion, while the rest may never build.
Author Note: The characteristics of the nest are as unique as their builders. Some Bettas will make large nests while others will decide that they only want small nests made up of small bubbles.
When kept in an aquarium, seeing your Betta build a nest is a sign that they are both healthy and happy, not to mention they are wanting to meet female fishes and begin the courting process.
Part of building the nest means that the male Betta fish has established a part of the tank as his territory.
To help facilitate the beta’s bubble nest building skills, it is important to include plants and caves it can either use for building or hide in while feeling stress.
Can Female Bettas Build Bubble Nests?
Females Bettas have the same labyrinth organ that allows for taking a breath that the male Betta has, however, the female will never instigate the construction of a bubble nest on their own.
It is well known that if a female finds a mate, they will sometimes assist the male in the building of a bubble nest. However, if housed alone, the female will never start to build a bubble nest in her tank.
Author Note: There are only two reasons it may appear that a female is building a nest. The first reason is that the fish is a short-finned male Beta fish.
The other reason is that while the female Betta fish will get a lot of their oxygen from breathing air from the top of the tank, stray bubbles are gathering at random and collecting in a way that appears to be a nest.
How Do I Provide the Best Conditions for Betta Fish Bubble Nests?
For the male Betta Fish to have success at building a bubble nest, it is important to pay attention to the water quality of your tank.
The surface water of your tank needs to be still. This is important because, in nature, Betta fish are found in ditches, shallow ponds, and rice paddies.
The splash zone created by some hang-on back filters can be enough to disrupt or destroy bubble nests under construction.
Top Tip: The best way to minimize the impact of hang on the back filters is by making sure the aquarium’s water is topped off.
Surface debris can provide both structures to the Betta Fish and a level of protection from water currents. In nature, Male Bettas weave their bubble nests around sticks, leaves, and floating plants.
Incorporating floating plants into your tank can help your Betta with the building. Choosing plants like Elodea, Crystalwort, and Hornworth will give your Betta more stability and better options for where to build its bubble nests.