Emerald betta

Betta smaragdina

Also known as Emerald green betta, Mekong fighting fish

FreshwaterFish

Emerald betta (Betta smaragdina) — --Acapella 09:31, 31 December 2006 (UTC) · CC BY-SA 3.0

Care at a glance

Temperature: 72–82°F (22–28°C)
pH: 6.0–7.5
Adult size: 2.4 in (6 cm)
Minimum tank: 11 gal (40 L)
Temperament: Aggressive
Social behavior: Solitary
Swim level: Middle
Difficulty: Easy
Breeding: Medium
Rarity: Common
Origin: Khorat Plateau (Isan), northeastern Thailand, and Mekong tributaries in central Laos
Family: Osphronemidae

Overview

Keep one fish, or a single pair if you have the experience, in a species tank of 40 liters or up. Males are aggressive and territorial, so never house two males together or mix them with other bettas, since they will flare and fight. They sit in the middle of the water column and are shy and easily outcompeted, so a single species setup suits them best. Hold the temperature from 22 to 28 C and the pH between 6 and 7.5, and keep the water level a couple of inches below a tight fitting lid so the fish can gulp humid surface air, since it is also an excellent jumper. Feed small frozen and live foods like daphnia, bloodworms, and brine shrimp. These are wild fish from a limited range, so never release one into local waterways and check your local rules before keeping or moving them.

In the wild

Emerald bettas come from the Khorat Plateau in northeastern Thailand and from Mekong tributaries in central Laos, where they live in soft, slightly acidic, dimly lit pools with heavy planting. To match that, give them a quiet, well planted tank of 40 liters or larger with floating plants like Salvinia or Riccia, driftwood, and leaf litter to stain the water with tannins. Keep the temperature from 22 to 28 C and the pH between 6 and 7.5, and go easy on the flow with a sponge or gentle filter.

Good to know

This is a labyrinth fish in the family Osphronemidae, a wild relative of the common betta that reaches about 6 cm. It breathes air at the surface using a labyrinth organ, and it is a bubble nesting species where the male builds and guards the nest. It is slightly hardier than Betta splendens but still wants stable, mature water.

Did you know

Despite the "fighting fish" reputation, the emerald betta is not hostile toward unrelated peaceful fish. The aggression is aimed almost entirely at its own kind, so a lone male will leave calm tankmates be while still treating any other betta as a rival to chase off.