Siamese Fighting Fish - Betta Splendens

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One of the most popular fish available, Siamese Fighting Fish (Betta Splendens) are often the number one fish on the wish-list of every new fish-keeper. These paradoxical fish are hardy yet delicate and can be peaceful and timid as well as aggressive and bullish

Male Siamese Fighting Fish Betta splendens

Siamese fighters are part of the Osphronemidae (Gourami) family, which are well known for their ability to take oxygen directly from atmospheric air through the use of a specially designed 'labyrinth' organ. The Siamese fighter originates from Thailand (Previously called Siam) and in its natural habitats it can be found in the still waters of floodplains, ditches, ponds, rice fields and rivers.

In these shallow tropical waters the temperature can regularly reach above 30C, so fighters do best when kept in warmer water (26-28C) in the aquarium. A long history of captive breeding has changed the fishes shape, colour and behaviour from the wild and bred-for-fighting forms, although elements of both remain. The commercial form has a smaller and slender body, greatly enhanced colour and longer fins, in fact fighters are available in almost any colour you can think of.

Are Siamese Fighters Aggressive Fish?

The name suggests that this fish is an aggressive species, but this is not the whole story. Two males will certainly fight until one is severely damaged or dead, so obviously males cannot be kept together, but aggression can also be seen towards other fish. In the vast majority of cases, this occurs when the fighters are kept with fish that exhibit long, flowing fins or bright colours, in which case the fighter may mistake them for other males.

Occasionally, an individual fighter can be a 'rogue' specimen and cause problems to its tank mates but this is a rarity and it is usually the other way round. The biggest difficulty with keeping fighters is the attentions of other fish, the long flowing fins and slow-swimming nature of the fighter presents an enticing target to take an easy nip at.

It is not just the usual nippy suspects that cannot resist temptation but also many fish that would normally be considered peaceful species. Some characins (tetras), barbs, and gouramies will seize the opportunity to take a nip, and if kept with such fish, a male fighter will soon become a stressed, ragged mess. Because of this you should always get good advice from your retailer or use the Think Fish Community Creator to check that the existing fish in your tank are compatible.


Are Siamese Fighters a Solitary Fish?

Siamese fighters are hardy, full of character, and are peaceful towards most other fish, so should they be considered a community fish? I would say not. The biggest problem is the attentions of other fish, and also the typical 'community aquarium' setup which may have lots of open spaces with a few items of decor and/or plants.

Siamese fighters do not seem to enjoy open spaces, preferring a densely occupied space with lots of vegetation and objects to explore. With such specific tank mate and surroundings needs, they should really be kept in an aquarium designed specifically for them. An ideal environment would be a small aquarium (45cm+) with dense planting and a few very peaceful tank mates such as small catfish and rasboras. In this environment the siamese fighter will feel quite at home and will become an active, interesting individual which can be appreciated beyond its stunning colour and form.

Responsible Siamese Fish Keeping

The American (and other countries) fish-keeping market is full of various bowls and 'mini-aquaria' which are often sold to house Siamese fighters, thankfully the trend has not caught on in the UK and we would hope that our welfare standards are too high for this to happen, although examples have been seen on more than a few occasions.

Because an animal will survive in a certain environment does not mean it is happy, or that keeping it in such a way is not cruel. The shallow, oxygen deficient, changing environments which fighters inhabit in nature have given the fish a hardy nature and an ability to withstand conditions in which other fish would quickly perish. It must be noted however, that these seemingly harsh natural conditions are part of a much larger ecosystem, with all kinds of stabilising forces, and are quite different to the aquarium. In a small bowl or other such environment there is no capacity for the breakdown of waste or stabilising of temperature and as such will be a very stressful and cruel environment to keep any fish.

Breeding Siamese Fighters

Siamese fighters are bubble-nesters, producing a floating mass of bubbles at the waters surface into which the eggs are laid and fertilised. Males will start the nest building process, indicating a willingness to breed, a female does not have to be present at this time and it is often best to keep females separate to avoid any unwarranted aggression from the male. Providing both fish have been fed a suitable diet with plenty of small live or frozen foods they should be in good breeding condition.

Once a female has become noticeably rounded in the belly and the male is nest building, the female can be introduced to a breeding tank, which should be at least 45cm, bare bottomed, and contain plenty of hiding spots for the female to retreat to. When the male has finished his nest he will display to the female and entice her under the nest, at this point the fish will circle each other and the male will curl his body around the females. During a 'spawning embrace' the male turns the female upside down where she will release eggs, which will sink to the bottom of the aquarium to be picked up by the male and placed in the nest. This process may be repeated a number of times and it can appear quite distressing to watch, as the female will often float at the surface or appear heavily stressed and abused, however, it is just the normal breeding process. The female should be removed after spawning so she can recover away from the male. The eggs will hatch after a day or so and become free swimming a few days later.

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