Lake Eacham Rainbowfish (Melanotaenia eachamensis) Care Guide
Melanotaenia eachamensis is an Australian rainbowfish once feared extinct at Lake Eacham, now Endangered and maintained through aquarist populations.
Compiled by Aquairi from published sources · Published · Updated
Overview
Melanotaenia eachamensis is a small rainbowfish of the family Melanotaeniidae, reaching about 6.5 cm standard length per FishBase. It was originally believed endemic to Yidyam (Lake Eacham) in Queensland and was once thought extinct; it survived in private aquarists' collections and was later found to have a wider natural range.
Taxonomy
- Family: Melanotaeniidae
- Genus: Melanotaenia
- Scientific name: Melanotaenia eachamensis
Habitat
Recorded from small creeks and crater lakes on the Atherton Tableland between the Barron and South Johnstone river systems, where it congregates along shallow margins among aquatic vegetation, fallen logs and branches. Wikipedia notes that predation by illegally introduced fishes such as the Barred Grunter and Mouth Almighty during the 1980s eliminated it from Lake Eacham itself.
Tank requirements
- Minimum tank volume: 120 L
- Temperature: 22-26 °C (72-79 °F)
- pH: 6.5-7.5
- GH: 8-20 °dGH
- School size: 8 or more individuals
- Lifespan: 4-6 years
Diet
FishBase places the species at a trophic level of about 2.9, consistent with an omnivorous diet. In aquaria it takes quality dry foods together with frozen and live invertebrates.
Compatibility
A peaceful mid-water schooler kept in groups of eight or more. It suits planted community tanks with other peaceful rainbowfish of similar size.
Conservation status
IUCN Red List: Endangered (assessed 2019). It is also protected in Australia under the EPBC Act 1999.
Breeding Lake Eacham Rainbowfish (Melanotaenia eachamensis)
Overview
Melanotaenia eachamensis was once believed to be endemic to Lake Eacham in Queensland, Australia, but has since been shown to have a wider range in the Barron and Johnstone River systems. It was initially thought extinct after Barred Grunter and Mouth Almighty were illegally introduced to the lake in the 1980s, then rediscovered in private aquarists' collections. It is listed as Endangered on the IUCN Red List, so captive breeding has real conservation value. FishBase gives a maximum length of about 6.5 cm.
Sexing
Breeding males show bronze to orange tones with almost-black margins on the dorsal and anal fins, and their fins are longer, more pointed and more brightly coloured than those of females. Females stay plainer with shorter, rounder fins.
Conditioning
As an omnivorous rainbowfish it takes varied dried, frozen and live foods. Conditioning the group on rich foods brings females into spawning condition and intensifies male display.
Breeding Setup
- The species spawns among bushy plants in the wild, so provide java moss and spawning mops in the aquarium.
- Keep either a single pair or a group of 2-3 females per male.
- FishBase lists a pH of 7.0-7.4 and a temperature of 23-27 degrees C.
Spawning Behavior & Trigger
Conditioned fish scatter adhesive eggs into the moss or mop over a series of days, the eggs attaching to the medium by fine threads in the manner typical of the genus.
Egg & Fry Care
The spawning medium can be moved to a separate tank to protect eggs and fry. As with related rainbowfish the small fry start on infusoria-type foods before taking free-swimming foods such as brine shrimp nauplii.
Common Challenges
Maintaining distinct, well-documented bloodlines matters for an Endangered species; mixing with other rainbowfish should be avoided. The history of this fish, once thought extinct in Lake Eacham after illegally introduced predators and later rediscovered in private aquarists' collections, shows how directly responsible captive breeding can support a species' survival. Clean water within the FishBase ranges and small first foods underpin fry survival.