The Siamese Fighting Fish is an aquarium icon known for its labyrinth organ (allowing air breathing) and vivid colors. While hardy, they require heated, filtered water (24-30°C). Males are solitary and fiercely territorial. Females are generally less ornate but can be kept in 'sororities' with strict precautions (minimum 5 females in 75L+).
At a Glance
Tank Requirements
Water Parameters
Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Male (Long Finned)
The classic commercial Betta with long, heavy fins. High territorial instinct, but low mobility limits their threat level in community tanks. Requires low flow to prevent exhaustion.
Differs in 3 traits from base species
Also known as: Veiltail, Halfmoon, Delta, Rosetail, Crown Tail, Standard, Double Tail
Male (Plakat / Short Finned)
Short-finned males closer to the wild form. Without the drag of long fins, they are fast, active hunters and significantly more aggressive towards tank mates than long-finned varieties.
Differs in 3 traits from base species
Also known as: Plakat, HMPK, Alien, Wild Type, Koi Betta, Samurai
Female
Can be kept singly (recommended) or in 'sororities'. A sorority requires 5+ females in a heavily planted 20-gallon (75L) tank minimum to spread aggression. Never keep 2, 3, or 4 females together as bullying will be lethal.
Differs in 4 traits from base species
Also known as: Sorority, Girl, Female Betta
Giant / King Betta
Selectively bred for massive size (up to 10-12cm). Their larger mouth size makes them a high predation risk for small schooling fish (Tetras, Rasboras) that standard Bettas ignore.
Differs in 5 traits from base species
Also known as: Giant, King, Half-Giant
Betta (Siamese Fighting Fish) Care Summary
The Betta (Siamese Fighting Fish), scientifically known as Betta splendens, belongs to the Anabantoids family group. Adults reach a maximum size of approximately 7 cm and have a compressed body shape with a moderate growth rate. Classified as semi-aggressive, this species primarily occupies the surface and mid-level zones of the aquarium and produces a low level of biological waste.
To thrive, the Betta (Siamese Fighting Fish) requires a freshwater only aquarium with a minimum volume of 19 litres and a tank length of at least 30 cm. Water temperature should be maintained between 24°C and 30°C, with a pH range of 6–8 and a general hardness of 5–20 dGH. A low water flow is preferred. To replicate their natural habitat, the tank should include plants - densely covered, plants - floating, and smooth gravel (sensitive barbels).
Only one Betta (Siamese Fighting Fish) should be kept per aquarium. Keepers should be aware that this species is not safe with ornamental shrimp, can be aggressive toward its own kind, will defend a territory within the tank, and is a known jumper, so a tight-fitting lid is essential. This species is available in 4 varieties: Male (Long Finned), Male (Plakat / Short Finned), Female, and Giant / King Betta. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Similar Species
Siamese Algae Eater
Crossocheilus oblongus
Famous for being one of the few freshwater fish that actively consumes Black Beard Algae (BBA). A torpedo-shaped, active bottom-to-midwater swimmer native to Southeast Asian streams. True Siamese Algae Eaters feature a distinct black horizontal stripe that extends all the way through the tail fin. As they mature, they can become lazy, preferring prepared foods over algae, and may occasionally chase other bottom dwellers.
Dwarf Gourami
Trichogaster lalius
A peaceful to semi-aggressive labyrinth fish native to South Asia. Famous for their brilliant metallic blue and red stripes. While generally suitable for community tanks, males are territorial toward each other and similar-looking fish. They are sensitive to water quality and prone to Iridovirus if stressed. Requires access to the surface to breathe.
Paradise Fish
Macropodus opercularis
One of the first ornamental fish in the hobby (pre-dating the Goldfish in Europe). Paradise Fish are stunning, hardy, subtropical Anabantoids. However, they are notoriously aggressive, often exceeding the aggression of Bettas. They are cold-tolerant and thrive in unheated indoor aquariums, but they will readily attack smaller tank mates, eat fry, and fight conspecifics to the death.
Discus
Symphysodon aequifasciatus
Known as the 'King of the Aquarium', Discus are stunning, heavily laterally-compressed cichlids. They are famous for their demanding husbandry, requiring high temperatures (28-32°C / 82-90°F), pristine water quality, and specialized diets. They are schooling fish that establish a strict pecking order and must be kept in groups to prevent intense bullying of a single weaker fish.
Guppy
Poecilia reticulata
One of the most iconic and widely kept aquarium fish. Renowned for their incredible colors, hardiness, and prolific breeding. As livebearers, they give birth to fully formed, free-swimming fry. Males constantly pursue females for mating; therefore, a ratio of at least 2 females per male is strongly recommended to disperse stress.
Pearl Gourami
Trichopodus leerii
Widely considered the most beautiful and peaceful of the large Gouramis. They feature a 'mosaic' of iridescent spots and a distinct black line running through the eye. Unlike their aggressive cousins (the Three-Spot Gourami), Pearls are generally gentle giants, though males can be territorial towards one another. They are thermophilic (love heat) and require floating plants to feel secure.