Delicate blue-eye

Care at a glance

Overview

Delicate blue-eyes are small, peaceful fish that feel secure in a group of eight or more, where the males flick their fins and show off their pale blue eyes and yellow-edged finnage. They occupy the middle and upper water and belong with other tiny, gentle species that will not outcompete them at feeding time. Because they are little, offer small foods such as micro pellet, crushed flake, frozen cyclops, and baby brine shrimp several times a day. They enjoy warm, soft, slightly acidic water and appreciate fine-leaved plants to weave through. Aim for a tank around 75 liters or larger.

In the wild

This blue-eye lives in the tropical north, across the Top End of Australia and into southern New Guinea, in clear, warm streams, lagoons, and swampy pools among dense vegetation. Those waters run soft and slightly acidic to neutral, which fits a pH of about 6 to 7.5 and a warm temperature between 25 and 32 degrees Celsius. Recreate it with soft light, plenty of fine and floating plants, some leaf litter or wood, and calm, clean water with only gentle movement.

Good to know

Pseudomugil tenellus is a blue-eye in the family Pseudomugilidae and reaches only about 5.5 centimeters. The name tenellus means delicate or tender, a fair description of this slight, short-lived fish. Males display to each other and to females with raised, spread fins rather than fighting. Like other blue-eyes it scatters small eggs among fine plants and roots over a long spawning window, giving no parental care, and the tiny fry need very small first foods, which makes breeding hard.

Did you know

Blue-eyes get their common name from the bright, reflective blue ring around the eye, which stands out even on such a small fish. Males show off by flaring their fins at each other in brief, harmless standoffs through the day.

Related species

• 

  Forktail blue-eye

  Pseudomugil furcatus

  2.2 in (5.5 cm)22 gal (85 L)75–82°F (24–28°C)

• 

  Pacific blue-eye

  Pseudomugil signifer

  2.8 in (7 cm)25 gal (95 L)68–79°F (20–26°C)

• 

  Spotted blue-eye

  Pseudomugil gertrudae

  1.5 in (3.8 cm)17 gal (65 L)70–82°F (21–28°C)
• Popondetta blue-eye

  Pseudomugil connieae

  2 in (5 cm)11 gal (40 L)75–82°F (24–28°C)
• Honey blue-eye

  Pseudomugil mellis

  1.4 in (3.5 cm)11 gal (40 L)68–82°F (20–28°C)
• Paska's blue-eye

  Pseudomugil paskai

  1.4 in (3.5 cm)11 gal (40 L)72–79°F (22–26°C)