Key Features:

Distinctive Appearance:
A striking color variant of the Siamese fighting fish, featuring metallic green iridescence often layered over deep blues or steel tones. The “alien” line is known for its reflective, almost shimmering armor-like look that changes under different lighting.

Behavior & Personality:
Highly individualistic and territorial, especially males. They are known for bold displays, flaring, and interacting with their environment and reflections. While intelligent and responsive, they should always be housed alone or very carefully managed in community setups.

Care Requirements:

Tank Conditions:
Requires a heated, filtered aquarium with stable conditions and minimal current. Ideal temperature range is 76–82°F (24–28°C). Prefers soft to moderately hard water with a slightly acidic to neutral pH (6.5–7.5). A tank with plants, resting spots near the surface, and gentle flow is ideal.

Diet:
Carnivorous/omnivorous. Best fed high-quality betta pellets as a staple, supplemented with frozen or live foods such as bloodworms, daphnia, and brine shrimp. A protein-rich diet helps maintain coloration and energy.

Compatibility:
Males are best kept alone due to extreme territorial aggression. Tank mates are only suitable in carefully chosen community setups with peaceful, non-fin-nipping species and plenty of space and cover. Avoid other male bettas entirely.

Size and Growth:

Adult Size:
Typically grows up to 2.5–3 inches (6–7.5 cm) in length.

Growth Rate:
Moderate growth, reaching full size and coloration within several months under stable, well-fed conditions.

Overview:

Betta splendens Alien Green is a selectively bred variant of the Siamese fighting fish, prized for its metallic green “armor-like” sheen and intense personality. It is best suited for beginner to intermediate aquarists, provided its need for warm, stable, low-flow conditions and (for males) solitary housing is respected.