Betta splendens, often sold as Siamese fighting fish, is one of the most popular first fish in Australian homes. Bettas are colourful, responsive and usually best kept on their own.
They are not suited to an unheated bowl. Bettas need a warm, filtered aquarium with gentle water flow, and with proper care they often live for three to five years.
The best approach is to prepare the tank before buying the fish. Here is a practical order to follow.
Before you buy: the setup checklist
Start with tank size. Peer-reviewed welfare research suggests that at least 10 litres is needed for a betta to show normal swimming behaviour.
Ten litres is a minimum, not an ideal target. A 20-litre aquarium is easier for a beginner to keep stable. LiveFish suggests about 35 litres for active short-fin, or plakat, bettas because they are strong swimmers.
Your basic shopping list includes:
- An aquarium of at least 20 litres with a secure, tight-fitting lid
- A submersible thermostat heater and separate thermometer
- A gentle sponge filter or adjustable-flow filter
- Water conditioner and a liquid water-testing kit
- Live or silk plants and smooth decorations without sharp edges
The lid detail most guides get half right
Fit a tight lid, because bettas jump and will find any gap. That part is standard advice.
What often goes unsaid is that the lid must not be airtight, and the water should sit two to three centimetres below it. Bettas breathe atmospheric air through an organ called the labyrinth, so they surface regularly and need that air gap to do it.
A sealed lid, or a tank filled to the brim, removes the one thing the fish cannot do without.
Cycle the tank before the fish arrives
Helpful bacteria grow in the filter and process fish waste. They convert toxic ammonia into nitrite and then into less harmful nitrate. This is called the nitrogen cycle, and it usually takes several weeks to establish.
Use a fishless cycling method and test the water regularly. The tank is ready when ammonia and nitrite return to zero after an ammonia source is added. RSPCA Australia recommends checking ammonia and nitrite every two to three days during the first six weeks.
Treat tap water with conditioner before adding it to the aquarium. Floating plants or tall stems can provide cover and give your betta resting places near the surface.
Heat, filtration and gentle flow
Bettas are tropical fish. Aim for a steady temperature of 24 to 26 degrees Celsius and use a thermometer to confirm it. A heater is still needed in many Australian homes because room temperatures can change sharply overnight.
Filtration removes debris and houses the bacteria that process waste. Choose a filter designed for the tank’s size, but avoid a strong current that pushes the fish around.
Long-finned males tire particularly quickly in fast-moving water. Direct the filter outlet toward the glass or use plants to soften the flow. Bettas generally tolerate a pH of about 6.5 to 7.8, but stability is more important than reaching a precise number.
Where to buy and how to choose a healthy fish
Once the aquarium is heated, filtered and fully cycled, you can buy bettas from LiveFish®, an online aquarium store, to compare varieties and read care information before acclimating your fish.
When assessing a fish, look for clear eyes, even breathing, intact scales and fins that are not tightly clamped. A healthy betta should respond to movement nearby. Avoid fish with white spots, obvious wounds, swelling or persistent difficulty swimming.
Males often have the long, flowing fins associated with the species, although short-fin males are also common. Females usually have shorter fins and can be just as territorial. Never keep two male bettas together in the same aquarium.
Fin type affects care as much as appearance. Halfmoon and veiltail males carry heavy fins that tire them in current and tear on rough decorations, while plakat males swim harder and need more room.
Acclimation day
Dim the aquarium lights and float the sealed bag for about 15 minutes to help equalise the temperature. If the fish was shipped, follow the supplier’s acclimation instructions before opening the bag.
For a fish collected locally, gradually add small amounts of tank water to the open bag over 20 to 30 minutes. Transfer the fish with a net and discard the bag water rather than pouring it into the aquarium.
Expect the fish to hide or sit still for the first day or two. That is normal and not a reason to intervene.
Can a betta have tankmates?
This is the question most new owners ask, and the honest answer depends on the tank rather than the fish.
In 20 litres, no. A single betta is the stocking limit, and adding anything else creates a territory problem in a space too small to escape.
In a planted tank of 40 litres or more, snails and a small group of corydoras often work. Add the tankmates first and the betta last, and keep a plan for separating them if it goes badly.
Avoid guppies in particular. Male guppies have bright, flowing fins, and a betta frequently reads them as a rival rather than a neighbour. Female sororities are an advanced project rather than a beginner one, and they fail more often than the internet suggests.
Feeding and weekly care
Use a quality betta pellet as the staple food and offer a small, measured serving once or twice daily. Pellet sizes vary, so follow the package guidance and remove uneaten food. Frozen brine shrimp or daphnia can provide occasional variety.
Bettas will eat well past the point of sense, and overfeeding is the most common husbandry mistake with the species. Two or three appropriately sized pellets per feed is usually enough, and one fasting day a week helps prevent bloating and constipation.
Each week, test the ammonia, nitrite and nitrate levels. Change about 10 to 25 percent of the water and lightly vacuum waste from the substrate. Larger changes may be needed if a test shows a water-quality problem.
Replacement water should be conditioned and close to the aquarium’s temperature. Rinse filter media in removed tank water when it becomes dirty or the flow slows. Tap water can kill the helpful bacteria, and replacing all the media at once can disrupt the cycle.
Reading your betta’s behaviour
A settled betta patrols the tank, investigates movement and rests on plants or decorations near the surface. Some resting is normal, particularly in older fish.
Persistent flaring at the glass is worth attention rather than admiration. The fish is responding to its own reflection and treating it as an intruder, which is stressful when it continues for hours. Dark backing on the tank, repositioning away from a bright window or adjusting the lighting usually resolves it.
Clamped fins, faded colour, hiding constantly or sitting on the substrate all point in the same direction. Test the water first, check the heater second and consider illness third.
One rule that is not negotiable
Never release a betta, or any aquarium fish or plant, into a creek, drain or waterway. Bettas are a tropical species with no place in Australian catchments, and released stock competes with native fish and spreads disease.
It also undoes exactly the kind of work being done to restore fish habitats in urban catchments around the country, where groups clear barriers to fish passage and revegetate creek banks so native species have somewhere to breed.
Releasing fish into public waters breaches state fisheries legislation without a permit, and dumping a pet fish is treated as animal cruelty. If you can no longer keep your betta, rehome it through an aquarium shop, a hobbyist club or an experienced keeper. Somebody will take a healthy betta.
Bringing it together
A warm, filtered and planted aquarium handles much of the routine work. Take time to choose a healthy fish, and use clear care information from a shop or supplier such as LiveFish to confirm that you can meet its needs.
Get the tank right before the fish arrives and most of what follows is maintenance rather than rescue.
FAQ
What do clamped fins or fading colour mean?
They can indicate poor water quality, an unsuitable temperature or illness.
What should I check first?
Test the water, make a partial water change if needed, then check the heater and filter flow.
Can decorations tear betta fins?
Yes. Replace sharp decorations with smooth ornaments or plants, and run a stocking over anything you are unsure about. If it snags the fabric, it will snag a fin.
Can a betta live with other fish?
Not in a 20-litre tank, where a single betta is the stocking limit. In 40 litres or more with dense planting, snails and small corydoras often work, though every betta is an individual and some will not tolerate company at all.
Why is my betta flaring at the glass?
It is reacting to its reflection. Occasional flaring is normal, but hours of it is stress. Reduce reflection with dark backing, move the tank away from direct light or change the lighting angle.
How often should I feed a betta?
Once or twice a day, offering only two or three appropriately sized pellets each time. Add one fasting day per week, since overfeeding causes more betta health problems than underfeeding.
When should I contact a veterinarian?
Seek advice from a veterinarian who treats fish if symptoms are severe, worsen or continue despite suitable water conditions.
