Max Size: 7cm

Emerald Betta (Betta smaragdina)

The vibrant Emerald Betta, Betta smaragdina, are rarely seen in the aquarium trade and are often mistaken for Betta smaragdina by the average hobbyist.

Despite their timidity, Emerald Bettas have a cheerful disposition. Many aquarists love this fish due to its unique appearance and the fact that it is more susceptible to disease since it has been bred less in captivity. However, their tanks and environments, such as tannins and plants, require more care than other Betta species.

Emerald Bettas are very territorial, and even if they are not looking to fight, they can attack or even kill other fish that become somewhat intrusive. This behaviour is particularly apparent during the breeding season. For this reason, these Bettas are not recommended for a community aquarium. Instead, its care requirements and disposition mean it is best kept alone or with very peaceful species.

Provided sufficient cover and a large enough tank, it is possible to keep more than one male per tank, though it is deemed best practice to isolate pairs for breeding purposes.

Emerald Bettas have an iridescent sheen that covers their entire body and extends outward towards their fins. Their primary body colour can vary between orange, red, green and blue however they always have the iridescent sheen of greeny-blue scaling. The length of these Bettas' fins tends to be shorter than other species of Betta and has striped patterning.


Emerald betta
Quick Facts
Scientific NameBetta smaragdina
Year Described1972
Other NamesEmerald Green Betta, Mekong Fighting Fish, Blue Betta
OriginsLaos, Thailand
Aquarium LevelTop
DifficultyBeginner - Intermediate
Best kept asLoners
ReproductionBubble nest
Lifespan5 - 7 years
Water Parameters
Water TypeFreshwater
PH5.5 - 7.5
GH2 - 10
TDS18 - 179
72 - 79℉
22.2 - 26.1℃

Natural Habitat

Chao Phraya River


In the home aquarium, the Emerald Betta will readily accept most good quality dried foods such as granules, flakes and sinking pellets. These modern food products have been developed to provide all adequate nutrition to maintain your fish's health and dietary requirements.

Providing additional foodstuffs such as live, frozen, and freeze-dried meals such as bloodworm, daphnia, and tubifex once or twice a week will provide additional benefits to your fish's health and well-being but is not a must for this fish.

It should be noted that bloodworms should only be given as an occasional treat and should not be used as the staple diet as they are difficult for fish to digest and can potentially cause blockages.

This fish is an omnivore in the wild, meaning it will consume some vegetable matter. Although most modern fish foods take this into account and include them in their products, you can still supplement your fish's diet with blanched vegetables such as spinach, broccoli, and zucchini. Ensure you do not overfeed your fish and remove any leftovers the following day.

Sexual Dimorphism

It is effortless to differentiate male from female Emerald Bettas. Males have much more pronounced colouration than females, and their fins are more comprehensive. In contrast, the females are duller, and their fins are shorter.

Other Bettas of interest

Red Skirt Betta(Betta Falx)
Siamese Fighting Fish(Betta Splendens)
Snakehead Betta(Betta channoides)
Spotfin Betta(Betta macrostoma)
Toba Betta(Betta Rubra)
Date Added: 27/01/2021 - Updated: 12/08/2022 13:55:05