Betta fish are beautiful, popular pets with a big personality! In fact, bettas are the most popular choice of pet fish after the traditional goldfish.
So, why can’t you have two or even three gorgeous bettas in one community tank?
Well, the answer to that is simple. Betta fish are not called Siamese Fighting fish for no reason! Bettas are highly territorial, and if you put two or more males together, they will fight, most likely until one fish is seriously injured or even killed. However, there is a way in which you can keep multiple bettas in one aquarium.
Read on to learn all about the pros and cons of betta dividers, including some DIY options you can make at home.
You will undoubtedly have seen bettas on display in your local fish store, housed in tiny boxes with dividers in between. That arrangement should only be for display purposes and is not suitable for a permanent display arrangement.
If you decide to go with a divided tank, there are certain basic welfare rules that you must follow if your fish are to be happy and thrive. Each part of the tank must provide a proper ecosystem for each fish.
Five gallons is the minimum tank size that we recommend for bettas. So, if you have a 10-gallon tank, you should divide it into two completely separate 5-gallon sections. A 20-gallon tank should be split into four individual ecosystems and so forth.
Things To Consider With a Split Betta Fish Tank
If you decide to go ahead and divide your betta tank, there are several options for you to consider.
- Buy a purpose-built, factory-made divided tank with silicone sealed glass sections.
- Buy a community fish tank divider system
- Make a DIY divider
There are pros and cons to each betta tank solution, which we will discuss later in this article.
Ideally, you want to use one filtration system and heater for the whole setup in a split fish tank, allowing water flow between sections.
Crucially, the visibility between each neighboring betta must be eliminated or drastically reduced. If the fish can see each other, both your bettas will likely become highly stressed and aggressive. As a result, the adult betta fish will continually flare at each other through the divider and attack the divider, potentially sustaining injuries that could kill the betta. So you want a tank with lots of places for your bettas to hide.
How Do You Make Homemade Aquarium Dividers?
So, do you want store-bought or DIY tank dividers? Although you can buy aquarium dividers, it can be better to make your own custom-designed version.
What You’ll Need:
- An aquarium
- Canvas mesh
- Binder report spines
- Aquarium silicone sealant
The best tanks to divide are long, shallow ones. Tall tanks don’t work well for bettas, as these labyrinth fish need easy access to the water surface to feed and breathe. You can use acrylic or glass, but glass aquariums tend to work best.
Bettas do best in long, shallow tanks that can be set up to replicate the fishes’ natural habitat. In the wild, bettas inhabit shallow, tropical water bodies that are usually poorly oxygenated. These labyrinth breathers need to take gulps of air at the water surface every so often to supplement the dissolved oxygen they take from the water. Also, long-finned bettas can struggle to get to the surface if kept in a very tall, deep tank.
In larger tanks, it’s generally easier to maintain stable water parameters in a single tank while accommodating divisions. Also, if you want to get a tank mate or two for your bettas, such as a snail or a few tetras, you will need a tank that’s larger than 10 gallons. Basically, the bioload in a 5-gallon divided tank would be too high, and there wouldn’t be enough space for more than one snail or shrimp.
If you use a long, shallow 20-gallon tank, you can create two 10-gallon compartments that have ample space for the betta and a few small tank mates to keep him company.
You can buy canvas mesh in craft stores and online. It’s used for needlepoint projects but works great for fish tank dividers, and it’s cheap to buy, too.
Measure the tank carefully but buy more canvas mesh than you need in case you don’t get it right the first time. Also, if the sheets are a bit too big, you can trim them to get the perfect fit. When you trim the mesh, make sure that the edges have no jagged edges that could injure your fish.
You’re going to use plastic binder report spines to secure the divider to each side of your tank.
You can buy binder report spines relatively cheaply in good stationery shops. Ideally, you want to buy the spines separately, as you won’t need the clear plastic report covers that they often come with.
You’ll need to cut each spine to fit snugly beneath the lip on each side of your aquarium. Once the canvas mesh is cut to size, finish the divider by adding lengths of plastic binder spine to support the edges.
If you want a more permanent means of securing the divider, you can use aquarium sealant to fix the spines into position. That’s also a sensible idea as it removes the risk of divider failure and the two fish getting into each other’s side of the tank. For added security, build up a bank of the substrate along the bottom of the divider on both sides.
To ensure that the two fish can’t see each other, we recommend using medium height, lush plants, and decorations against the mesh. You can also double-up the mesh or use a dark color.
Center Divider Compartment
Another option for dividing a betta tank is to create two separate areas with a small corridor between them. Here, you can put your plants and your heater.
That arrangement works very well as it creates a good barrier that the fish can’t easily see through, puts plenty of space between the two territories, and allows for the same water circulation, filtration, and heating to be used for both areas of the divided tank.
Jump To It!
As you know, bettas are excellent jumpers. In the wild, especially during the dry season, betta fish sometimes need to leap from one body of water to another to search for food or avoid rival males. So, bear that in mind when creating your divided betta tank.
If your divider isn’t high enough or the water level is such that the betta can jump and clear the divider, trouble will surely follow.
Diseases In A Multiple Betta Tank
A divided betta tank does mean less tank maintenance since you only need to carry out one lot of water changes and tank cleaning every week.
However, a divided tank also increases the risk of spreading diseases that could affect both your bettas and other tank residents because both mini tanks share the same water. To stay safe, you need to have a quarantine tank on standby so that you can remove one betta if he becomes sick.
If you buy any new fish or plants, you need to follow the correct quarantine protocols and acclimation routine before putting anything new into your divided betta tank. Betta fish that have been kept in cramped, less than ideal conditions in fish stores are prime candidates for carrying stress-related diseases. So, you must resist the temptation to put a new fish straight into your tank.
Are Divided Tanks Good For Bettas?
Once you’ve split your betta tank, you need to observe it closely for a few days, watching how each betta reacts to his new environment and his neighbor.
Clearly, if the two fish can see each other, there are likely to be stress-related problems. However, if you have two bettas that are chilled out dudes, they have a few small tank mates for company, and you equip each compartment with plants, caves, and toys, it’s unlikely that you’ll have any problems.
Monitoring Your Divided Betta Tank
Once you’re all set up, you’ll need to carry out daily checks to ensure that the environment is safe for the fish.
First of all, look to check for breaches in the divider. Sometimes, a feisty fish or curious snail can push a small hole in the edge of the divider where it joins the side of the aquarium, allowing the bettas to get through. Fix any damage immediately!
The water level in the tank should be a few inches lower than the top of the divider to prevent the bettas from leaping across. And remember, make sure your tank lid is tight to avoid picking bettas up off the floor.
In case of accidents, keep a net, a cup, or your quarantine tank within easy reach. That way, if one fish does get into the opposite compartment, you can separate them quickly.
If a week goes by and both the fish are still constantly agitated, flaring at one another, and clearly stressed out, you’ll need to consider adding more planting or decorations to reinforce the divider.
It is possible to keep two or more betta fish, as long as you divide a long, shallow tank correctly so that the fish have plenty of space and can’t see each other.
The most important aspect of keeping multiple bettas in split betta tanks is that the fish can’t see each other or get to each other. To achieve that, you can place one divider down the center of the tank, covering it with plants and decorations so that the fish can’t see each other. Alternatively, you might prefer to set up a narrow corridor between the two betta compartments, filling it with lush plants.