Blue neon carnival gudgeon

Hypseleotris leuciscus

Also known as Leuciscus carp gudgeon

FreshwaterFish

Blue neon carnival gudgeon (Hypseleotris leuciscus) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 75–82°F (24–28°C)
pH: 6.5–7.8
Adult size: 2 in (5 cm)
Minimum tank: 14 gal (54 L)
Temperament: Mostly peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: No record
Rarity: Rare
Origin: New Guinea lowland waters
Family: Eleotridae

Overview

This is a small, active carp gudgeon that lives out in the open midwater rather than sitting on the bottom like most of its sleeper relatives. Keep it in a group of at least six, and better eight or more, where the males color up and display to each other. It is peaceful and community safe with other small, calm fish, though its mouth means very tiny tankmates and fry are not a good mix. Feed small foods: fine flakes and micro pellets plus frozen daphnia, cyclops, and baby brine shrimp. A planted tank of around 54 liters with open swimming space and gentle flow keeps a shoal settled.

In the wild

The blue neon carnival gudgeon comes from lowland fresh and slightly brackish waters of New Guinea and its neighboring islands, where it gathers in loose shoals among plants and submerged roots in still to slow current. A planted aquarium with soft to neutral, warm water suits it, around 24 to 28 C and roughly pH 6.5 to 7.8. Dark substrate, floating cover, and a few open lanes to swim bring out the best color.

Good to know

Hypseleotris leuciscus is a member of the sleeper goby family Eleotridae, reaching only about 5 centimeters. Unusually for the family, carp gudgeons are shoaling, midwater fish rather than solitary bottom sitters, and displaying males flash blue and silver sheens with raised fins. Its captive breeding is not well documented, so it is kept mainly as a peaceful display shoal rather than a fish to spawn.

Did you know

The carp gudgeons are the restless athletes of a family famous for sitting still. While its cousins spend the day propped on their fins in one spot, this little sleeper schools out in open water like a minnow.

Tank mates

Blue neon carnival gudgeon is a mostly peaceful, schooling species that keeps to the middle. These picks match on water type, temperature, pH, size and temperament.