Boesemani Rainbowfish Care Guide
Boesemani Rainbowfish (Melanotaenia boesemani) are one of the most spectacular freshwater fish in the hobby. Males develop a sharp color split: vivid electric blue or violet on the front half, bright orange or yellow on the back half. They are also active, peaceful schoolers that work brilliantly in larger planted community tanks. The catch: they need space, and they need a group. A single Boesemani in a small tank is a sad fish; a school of seven in a 55+ gallon is a showpiece.
Quick Stats
- Scientific name: Melanotaenia boesemani
- Adult size: 4-4.5 inches
- Minimum tank: 55 gallons; 75+ for a proper school
- Temperature: 74-82°F
- pH: 7.0-8.0
- Hardness: 9-19 dGH
- Diet: Omnivore
- Temperament: Peaceful, active schooler
- Lifespan: 5-8 years
Tank and water
Boesemani come from a small lake system in West Papua, Indonesia. They are open-water swimmers and demand horizontal swimming space – a six-foot-long 75-gallon outshines a four-foot-tall 75 for them. Plant the back and sides heavily, leave the front and middle open, and use sand or fine gravel. Driftwood and rounded river rocks suit them. A tight lid is essential; they jump when startled.
Water should be moderately hard and slightly alkaline. Our Key West tap is on the harder side and suits them perfectly. Soft-water keepers may want to add a bit of crushed coral or remineralize RO water. Stable parameters and good filtration matter more than chasing specific numbers. They appreciate moderate to strong current – they evolved in clear, well-oxygenated lakes.
Stocking and tankmates
Always keep Boesemani in groups of six or more, ideally with more females than males. A solo Boesemani hides and fades; a single male with only females will dull out. Multiple males will color up best, sparring harmlessly for female attention. They are completely peaceful toward other species but their size and active swimming can stress smaller, calmer tankmates.
Good tankmates: other rainbowfish species (turquoise, dwarf neon), congo tetras, large rasboras, peaceful larger barbs (rosy, cherry), angelfish, and big peaceful catfish (bristlenose, peaceful Corydoras). Avoid fin-nippers, very small tetras (which look like food in a large tank), and aggressive cichlids.
Diet
Boesemani are not picky. A quality flake or pellet (we like New Life Spectrum) as the base, plus frozen bloodworms, daphnia, mysis, and brine shrimp two or three times a week. Color-enhancing foods (with astaxanthin) bring out the orange. Feed twice a day; they have fast metabolisms and constant activity to support. Vary the diet – monotony dulls them.
What you are buying from us
Juvenile Boesemani are mostly silver – the color does not develop until 6-12 months as they mature. Do not be discouraged when your fish arrive looking plain. Give them clean water, a big group, varied food, and time. Adult coloration is worth the wait. Adult males in good condition are unmatched in freshwater.
Ordering from us
Rainbowfish ship well as juveniles. We follow our standard Shipping & Acclimation procedure and drip acclimate over 45-60 minutes. If you are setting up a new tank specifically for a school of Boesemani, email us at help@jojoaquatics.com before ordering – we are happy to coordinate so you get a balanced group of males and females.
— The JoJo Aquatics team, Key West, Florida
