Parkinson's rainbowfish

Care at a glance

Overview

Keep them in a group of six or more in a tank of at least 200 liters, ideally around four feet long, since they are large and active and need the length to swim. They are mostly peaceful but on the pushy side, so the school stays in the middle of the water column and can intimidate shy, slow tankmates at feeding time. Hold the temperature from 24 to 28 C with hard, alkaline water at a pH of 7 to 8 and good oxygenation. Feed quality flakes and pellets with frozen foods like brine shrimp and daphnia to bring out their color. Pick tankmates that are robust and quick enough to hold their own, and skip the timid ones.

In the wild

Parkinson's rainbowfish come from clear, fast-running streams in southeastern Papua New Guinea, between the Kemp Welsh River and Milne Bay. That water is hard, alkaline, and well oxygenated, so set up a tank with some current from the filter or a powerhead and keep the pH between 7 and 8. Hold the temperature from 24 to 28 C. Leave plenty of open horizontal space down the middle for them to swim, with planting pushed to the back and sides.

Good to know

This is a rainbowfish in the family Melanotaeniidae, growing to about 11 cm as an adult. It is an egg scatterer that lays onto fine-leaved plants over a stretch of days, with no parental care. The fry are tiny at hatching and need very small first foods. Tank-bred stock turns up in the trade alongside wild-line fish.

Did you know

Males spar by flaring at each other to settle who looks best, flashing color and spreading their fins without doing any real damage. In a big group you will see this most at feeding and in the morning when the light comes up, then it settles down again once the pecking order is sorted.

Related species

• 

  Australian rainbowfish

  Melanotaenia fluviatilis

  4.3 in (11 cm)30 gal (115 L)68–77°F (20–25°C)

• 

  Boeseman's rainbowfish

  Melanotaenia boesemani

  4.3 in (11 cm)30 gal (115 L)81–86°F (27–30°C)

• 

  Lake Kutubu rainbowfish

  Melanotaenia lacustris

  4.3 in (11 cm)29 gal (110 L)68–77°F (20–25°C)

• 

  Duboulayi's rainbowfish

  Melanotaenia duboulayi

  4.7 in (12 cm)30 gal (115 L)64–82°F (18–28°C)

• 

  New Guinea rainbowfish

  Melanotaenia affinis

  4.7 in (12 cm)30 gal (115 L)68–86°F (20–30°C)

• 

  Western rainbowfish

  Melanotaenia australis

  4.7 in (12 cm)30 gal (115 L)72–81°F (22–27°C)