Breeding Parkinson's Rainbowfish (Melanotaenia parkinsoni)

Breeding Melanotaenia parkinsoni: distinct pairing, sexing by the golden-orange male, warm alkaline water, plant or mop spawning and fry care.

Overview

Melanotaenia parkinsoni is a rainbowfish endemic to Papua New Guinea between the Kemp Welsh River and Milne Bay, where it lives in lowland rainforest streams. FishBase reports a maximum length of 11.0 cm for males and 9.0 cm for females, and lists the species as showing distinct pairing during reproduction. It is Near Threatened on the IUCN Red List.

Sexing

Males have deeper bodies and more extended fins than females, with the rear half of the body taking on a reflective golden-orange tone over a dark lavender base and rosy chest. Females are noticeably plainer. The intense colour of mature males makes pairing easy to judge.

Conditioning

As an omnivore the species takes dried, frozen and live foods; conditioning a group on varied live and frozen foods brings females into condition and intensifies male display before spawning.

Breeding Setup

• Use fine-leaved plants such as java moss or nylon spawning mops; no substrate is required.
• FishBase gives a spawning-water profile of pH 7.5-7.8.
• FishBase lists a preferred temperature range of 26-30 degrees C.
• Gentle air-driven filtration keeps the water oxygenated.

Spawning Behavior & Trigger

FishBase records distinct pairing for this species. As a rainbowfish it scatters adhesive eggs over fine plants or mops, the eggs hanging from the medium by small threads, and continues to deposit eggs over a series of days rather than all at once.

Egg & Fry Care

Spawning media can be moved to a separate tank for hatching. As with related rainbowfish, the small fry begin on infusoria-type foods and move onto free-swimming foods such as brine shrimp nauplii once large enough.

Common Challenges

This is one of the larger rainbowfish, reaching up to 11 cm by FishBase, so provide ample space for the adults and a long, well-planted spawning tank. Its natural home in lowland rainforest streams points to warm, alkaline water within the FishBase ranges to support active spawning, while clean water and small first foods are key to fry survival.