Fellow Creatures
Saltwater Fish

Sixline Wrasse

Pseudocheilinus hexataenia

Active, jewel-toned hunter of reef pests  ·  Beginner

Sixline Wrasse

Brian Gratwicke · CC BY 2.0 — Wikimedia Commons

Lifespan
4-7 years
Adult size
7-8cm (3in)
Min. habitat
Aquarium 110L+ / 30gal+
Social needs
One per tank in most systems
Diet
Carnivore, micro-invertebrates
Time
Low
Cost
Medium

Overview

  • The Sixline Wrasse is a small, fast, jewel-toned fish striped orange and blue, popular for its hardiness and appetite for reef pests.
  • It is constantly active, darting through rockwork in search of food.
  • It is reef-safe and helps control pyramidellid snails and some flatworms.
  • Easy to keep, it suits beginners, though its bold temperament can grow more aggressive as it matures.

Housing

  • House in an established reef of at least 110L (30 gallons) with abundant live rock full of crevices to hunt and shelter in.
  • A mature tank with a good population of micro-invertebrates provides natural foraging.
  • Keep temperature 24-27C (75-81F), salinity 1.024-1.026, pH 8.1-8.4, and ammonia and nitrite at zero.
  • Plenty of rockwork lets this active fish exercise its natural hunting behaviour.

Diet

  • A carnivore that hunts copepods, amphipods, small worms, and other micro-invertebrates among the rocks.
  • Supplement with frozen mysis and brine shrimp, marine flakes, and pellets once or twice daily.
  • A mature tank with a healthy pod population supports natural grazing between feedings.
  • It readily accepts prepared foods, making it simple to keep well-fed and active.

Health

  • Hardy and disease-resistant, one of the more forgiving marine fish, though quarantine remains best practice.
  • Stable water and a varied diet keep it healthy and well coloured.
  • Watch for hiding, faded colour, or reduced appetite as signs of stress or poor conditions.
  • It can also jump, so a secure lid prevents the most common cause of accidental loss.

Temperament

  • Active and bold, it becomes increasingly territorial and aggressive with age, sometimes harassing newly added or timid fish.
  • Add it last to a community so existing fish are established, and keep only one per tank.
  • Reef-safe with corals and most invertebrates, it leaves desirable inverts alone while hunting pests.
  • Its assertive nature means careful tankmate selection in smaller or peaceful systems.

A good fit for

  • Beginners wanting a hardy, active fish
  • Reef tanks needing pest control
  • Mature tanks with healthy pod populations
  • Keepers wanting colour and movement

Common mistakes to avoid

  • Grows territorial and aggressive with age
  • Add last so it cannot dominate
  • Known jumper; needs a secure lid
  • May bully timid or newly added fish
Open in the interactive browser → Find an ethical store Find an exotic vet

More Saltwater Fish guides

Ocellaris Clownfish
Ocellaris Clownfish
Amphiprion ocellaris
Beginner

Hardy, beginner-friendly reef-tank clownfish

6-10 yearsRead guide →
Royal Gramma
Royal Gramma
Gramma loreto
Beginner

Purple-and-gold peaceful reef basslet

5-7 yearsRead guide →
Firefish Goby
Firefish Goby
Nemateleotris magnifica
Beginner

Slender dartfish with a flicking dorsal flag

3-5 yearsRead guide →
Yellow Watchman Goby
Yellow Watchman Goby
Cryptocentrus cinctus
Beginner

Sand-sifting goby that shares a pistol-shrimp burrow

4-6 yearsRead guide →
Pajama Cardinalfish
Pajama Cardinalfish
Sphaeramia nematoptera
Beginner

Peaceful nocturnal cardinalfish that lives in groups

4-5 yearsRead guide →
Green Chromis
Green Chromis
Chromis viridis
Beginner

Active blue-green shoaler for a peaceful reef

8-15 yearsRead guide →