TankBud

Harlequin sharkminnow

Labeo cyclorhynchus

Also known as Harlequin shark, Variegated shark, Calico shark

FreshwaterFish

Harlequin sharkminnow (Labeo cyclorhynchus)
The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature
73–81°F
23–27°C
pH
6.0–7.5
Adult size
6.3 in
16 cm
Minimum tank
66 gal
250 L
Temperament
Aggressive
Social behavior
Solitary
Tankmates
With caution
Swim level
Bottom
Diet
Omnivore
Difficulty
Medium
Breeding
No record
Rarity
Rare
Family
Cyprinidae
Origin
Congo basin

Overview

The harlequin sharkminnow is a solitary, territorial grazer that claims a patch of the tank bottom and defends it hard. It is best kept by someone with a little experience.

Did you know

The harlequin sharkminnow stands out among its Labeo relatives, which mostly wear plain, solid colors. Its blotchy, camouflage-style pattern of mottled cream and black gives it the trade names harlequin and variegated shark.

Caring for the harlequin sharkminnow

Give a harlequin sharkminnow 66 gal (250 L) or more, with a sandy floor, plenty of driftwood and rounded stone. Add caves it can adopt as a base, and broken-up hardscape that splits the floor into territories. Those visual barriers help take the edge off its territorial streak.

Run a steady current, and keep the water at 73 to 81°F (23 to 27°C) and a pH of 6.0 to 7.5. It works surfaces for algae and aufwuchs, so feed algae wafers, sinking pellets and some meaty frozen foods.

Keep this fish one to a tank. It will not tolerate another of its kind or any similar shark-shaped fish, which it chases relentlessly. Sturdy, dissimilar midwater and upper fish that stay out of its ground-level territory are fine. Other bottom dwellers and lookalikes are not.

Its breeding in aquariums is not documented. Adults are too aggressive to pair up easily.

Good to know

Labeo cyclorhynchus is an African member of the carp family, Cyprinidae, and its species name means round snout. It fills the same aquarium niche as the Asian red-tailed and rainbow sharks, as another sturdy, territorial cyprinid grazer.

In the wild

The harlequin sharkminnow lives among wood and rock in tributaries of the Congo basin in central Africa. The water there is warm and flowing.

Common questions

What size tank does a harlequin sharkminnow need?

A harlequin sharkminnow needs at least 66 gal (250 L). It spends most of its time in the bottom.

What temperature and pH does a harlequin sharkminnow need?

A harlequin sharkminnow is comfortable at 73–81°F (23–27°C) with a pH of 6.0–7.5.

What does a harlequin sharkminnow eat?

A harlequin sharkminnow eats algae wafers, sinking pellets and some meaty frozen foods. It also grazes algae and aufwuchs from surfaces in the tank.

How big does a harlequin sharkminnow get?

An adult harlequin sharkminnow reaches about 6.3 in (16 cm).

How does a harlequin sharkminnow breed?

The harlequin sharkminnow has no documented breeding in aquariums. Adults are too aggressive to pair up easily.

Related species