About the Blue Rainbowfish
name: blue rainbowfish (melanotaenia lacustris)
max size: up to 4–5 inches
water parameters: pH 7.0-8.0, temperature 75-82°F, moderately hard to hard water
diet: omnivorous – thrives on high quality flakes, micro pellets, and color-enhancing foods; supplement with live or frozen foods such as brine shrimp, daphnia, bloodworms, and mosquito larvae to promote vibrant coloration and healthy growth
temperament: peaceful, active, and social; best kept in groups of at least 6, preferably 8–10 or more, to encourage natural schooling behavior and reduce stress
tank setup: spacious aquarium of at least 55 gallons with plenty of open swimming space, live plants, driftwood, and moderate water circulation; excellent filtration, stable water conditions, and a tightly fitting lid are recommended
compatibility: excellent with other peaceful community fish such as rainbowfish, larger tetras, rasboras, peaceful barbs, gouramis, and corydoras; avoid aggressive species and very small or delicate fish that may be intimidated by their energetic swimming
behavior: highly active schooling fish that spends most of its time swimming through the middle and upper levels of the aquarium; males frequently display their fins and intensify their coloration when competing for attention or courting females
fun fact: blue rainbowfish are native to Lake Kutubu in Papua New Guinea and are also known as Lake Kutubu Rainbowfish. Mature males can develop an incredible metallic turquoise-blue coloration that changes in intensity depending on lighting, mood, and social interactions, making them one of the most striking naturally blue freshwater aquarium fish.
