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Maximum size : 7 cm

Emerald Betta - Betta smaragdina : Complete Fish Profile & Care Guide

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The stunning Emerald Betta fish (Betta smaragdina) is a rare sight in the aquarium trade, often mistaken for other Betta smaragdina varieties by the average hobbyist. However, despite their shy demeanour, these fish are known for their cheerful disposition, captivating the hearts of aquarists worldwide with their unique appearance and susceptibility to disease due to their lesser breeding in captivity. However, it is important to note that caring for Emerald Bettas requires extra attention and diligence, particularly regarding their tanks and environments, which may include tannins and plants. As a highly territorial species, Emerald Bettas may attack or even kill other fish that they perceive as a threat or an intrusion into their space, particularly during the breeding season. Therefore, keeping them in a community aquarium is not recommended, but rather alone or with peaceful species. It is possible to house more than one male in a tank if necessary, provided there is sufficient cover and space. However, best practice dictates isolating pairs for breeding purposes. The Emerald Bettas feature an iridescent sheen encompassing their entire body, extending towards their fins. The primary body colour may vary between orange, red, green, and blue, while the iridescent sheen is predominantly green-blue. Compared to other Betta species, the length of their fins is relatively shorter, with unique striped patterning.

Emerald Betta Photos

Sexual Dimorphism

Distinguishing between male and female Emerald Bettas is a simple task. The males exhibit a significantly more prominent and vivid colouration than their female counterparts, coupled with broader fins. Conversely, the females display a relatively subdued hue and possess shorter fins.

Quick Facts

Scientific NameBetta smaragdina
Year Described1972
Other NamesEmerald Green Betta, Mekong Fighting Fish, Blue Betta
OriginsLaos Thailand
Max Size7 cm
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

The Emerald Bettas are indigenous to the tropical regions of Laos and Thailand in Southeast Asia, where they can be spotted in water bodies such as the Chao Phraya River and the Mekong River. These vibrant fish prefer to inhabit tranquil or slow-moving waters, such as rice paddies, ditches, swamps, ponds, and streams. These aquatic environments are typically enveloped in a dense canopy of submerged marginal or surface vegetation and are occasionally characterized by low dissolved oxygen levels. The substrate of their natural habitat can range from leaf litter to sand, mud, or deep sediment, providing a diverse and dynamic living space for these fascinating creatures.
 Chao Phraya River - Thailand
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How to breed the Emerald Betta

Emerald Bettas are bubble-nesting species and are relatively easy to breed. The male displays breeding readiness by constructing a bubble nest in a secure aquarium area, either on the aquarium sides or attached to plants or decor, to house his eggs. This nest serves as a protective haven for the eggs until they hatch into fry. In preparation for breeding, the female 's colours fade, and she develops vertical bars and a noticeably fuller belly. Following the completion of mating, the female will depart, and any eggs that fall will be collected by the male, who will subsequently place them in his bubble nest. Removing the female from the breeding tank at this juncture is advisable, as the male may become aggressive towards her. The eggs will typically hatch within a span of 1 to 2 days, and the fry will rely on their yolk sac for nourishment for 3 to 4 days. Thereafter, the male will assume responsibility for caring for his offspring until they reach the free-swimming stage, which usually occurs around 4 to 5 days later. At this juncture, the male should be removed. Initially, the fry will require baby brine shrimp or microworms for sustenance, with their dietary needs gradually increasing as they mature.

Diet & feeding

For your Emerald Betta, it is advisable to provide high-quality flakes, granules, and Betta pellets as a staple diet, supplemented by small, live, and frozen foods such as bloodworm, artemia, and daphnia. This nutritional regimen will ensure optimal colour and overall health. However, it is crucial to exercise caution and not overfeed your Emerald Bettas, as they have a susceptibility to obesity, which can lead to severe health consequences. A controlled and balanced feeding schedule will aid in maintaining your fish 's ideal weight and well-being.

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