The Yukase Rainbowfish, also known as Boesemani 'Yukase' Rainbowfish, is a variant of the Boesemani Rainbowfish (Melanotaenia boesemani), known for its striking and vibrant colors. These freshwater fish are endemic to the Ayamaru Lakes in West Papua, Indonesia, and are highly sought after in the aquarium trade.
### Habitat and Tank Requirements
Yukase Rainbowfish thrive in well-vegetated tanks with ample open swimming space. They prefer water temperatures between 75-82°F (24-28°C) and a pH range of 6.0-8.0. The ideal tank setup should have moderate water flow and be well-filtered to maintain water quality. A tank size of at least 30 gallons is recommended for a small group, but a larger tank is preferable to accommodate their active nature and social behavior
### Diet
These omnivorous fish enjoy a varied diet that includes high-quality flakes, pellets, and live or frozen foods such as bloodworms, brine shrimp, and daphnia. They also benefit from the occasional vegetable matter like spinach or zucchini. Feeding them twice a day with portions they can consume within a few minutes helps maintain their vibrant colors and overall health [oai_citation:3,Care Guide for Boesemani Rainbowfish — Tank Setup, Breeding, and More
Breeding Yukase Rainbowfish is relatively straightforward. Males will display more intense colors during the breeding season to attract females. The eggs are typically laid on plants or substrate and hatch within a week. The fry require microscopic live foods initially, transitioning to larger foods as they grow [oai_citation:5,Boesemani Rainbowfish: Care Guide, Feeding, Tank Size [2022]](https://theaquariumguide.com/articles/boesemani-rainbowfish).
### Tank Mates
Yukase Rainbowfish are peaceful and can be kept with other similarly sized, non-aggressive fish. Suitable tank mates include other rainbowfish, loaches, barbs, peaceful catfish, gouramis, danios, and medium-sized livebearers. They should be kept in schools of at least six to ensure they are comfortable and exhibit natural behaviors [oai_citation:6,Care Guide for Boesemani Rainbowfish — Tank Setup, Breeding, and More
