Tank size

Tanks for housing Siamese fighting fish should be at least 15 litres in volume, with an optimal size of 20 litres or greater. Small tanks or fish bowls do not provide adequate space or a healthy environment for Siamese fighting fish. These fish are known to be intelligent and curious, and small bowls do not meet the fish’s behavioural or physiological needs.

Siamese fighting fish are excellent jumpers so the tank should be fitted with a lid to prevent escape. Siamese fighting fish require occasional surface air, even if water oxygen is plentiful, so there must be some space between the water and the tank lid in which to take in air.

Tanks housing additional fish should be in excess of 40 litres so that individual territories can be established. This will reduce chances of aggression and/or stress between the species. Each tank should only contain a single male Siamese fighting fish.

Filter

A filter of appropriate size for the tank with adjustable flow is needed. Siamese fighting fish prefer low flow as this mimics their natural habitat. Filters are crucial in providing circulation, aeration and filtration of the water. Filters assist by removing large waste particles and by breaking down toxic waste products. When the tank water is passed over the filter media, beneficial aquarium bacteria convert the toxic ammonia released from decaying fish waste into less harmful nitrates. This is known as a biological filter, and is essential to the health of any aquarium. These bacteria take weeks to establish in a new aquarium, and can be lost quickly by completely cleaning a tank, which is what often occurs in small tanks and bowls.

Heater and thermometer

Siamese fighting fish are from a tropical climate, so proper heating is essential. Normal room temperature is not suitable as this is generally too cold. Room temperatures can also fluctuate, and this can be stressful to the fish.

The tank should be heated using a submersible aquarium heater and the temperature should be kept at around 24°C.

Small fish bowls are usually too small to fit a suitable heater and thus cannot properly regulate and maintain a constant ideal temperature. Some bowls/tanks are sold with small lamps above them, suggesting that this will provide adequate heat. However, these lamps are usually switched off at night and the heat provided may be either insufficient or excessive depending on the surrounding area/climate the bowl is kept in. A submersible aquarium heater is the only way to achieve and maintain a constant and appropriate temperature for Siamese fighting fish.

Water quality

Good water quality is essential for any aquarium. You should use a quality liquid water conditioner to remove chlorine and chloramine from tap water before adding it to your tank. Use GH ‘General Hardness’ and KH ‘Carbonate Hardness’ supplements. These will vary depending on your local water supply. Siamese fighting fish require a pH of around 7.0, GH 7-9º, KH 5-8º.

You should regularly test your water for pH, GH, KH, ammonia, nitrite and nitrate. Some liquid solutions are available that are effective at cycling tanks quickly while adding fish to the tank.

Tank maintenance

Partial water changes of approximately 10% should be performed once per week, using a gravel vacuum to remove waste and uneaten food from the substrate. At this time the sides of the tank can be wiped with an aquarium safe sponge and filter media and/or decorations can be cleaned in old tank water.

The tank should be kept out of direct sunlight to inhibit algae growth and excessive heat. Aquarium lights should be kept on for a maximum of 12 hours to provide fish with adequate rest time. This will also help to reduce the chance of algae forming.

Environmental enrichment

Siamese fighting fish are intelligent fish and require an interesting and varied environment. They originate from densely vegetated areas and tend to prefer a tank with several plants, real or artificial, and/or other forms of cover in which to explore, rest and hide if they feel threatened. This will provide a stimulating environment to explore and reduce stress to the fish. Siamese fighting fish will be more active, inquisitive and interesting to watch when they feel secure in their surroundings.

To ensure fins are not torn, gravel should be smooth and decorations such as silk or live plants should have no rough edges. Male fish with long fins are particularly prone to fin tears. Sharp edges and points on some decor and driftwood can be sanded gently to make it safe.

As Siamese fighting fish require surface air supplementation to survive, being close to the surface is beneficial when resting. Providing tall plants with large leaves on which fish can rest at night can assist with this.

Mirrors should never be left in a tank as constant ‘flaring’ of fins by males can cause stress and exhaustion.

Behaviour

It is normal for some Siamese fighting fish to ‘hang out’ or rest in one area or for a while, with some fish being more active than others. However, a healthy fish is always responsive, moderately active and inquisitive. Any fish which is constantly hiding or appearing lethargic and unresponsive to its owners is likely to be stressed or suffering illness and should be provided with appropriate medical care.

Male fish will sometimes construct bubble nests as a sign they are ready to breed. These appear as a cluster of small bubbles of various sizes on the surface of the tank in a corner or area where there is some cover. This is a normal behaviour.