TankBud

Scissortail dartfish

Ptereleotris evides

Also known as Scissortail Goby, Blackfin Dartfish, Arrow Dartfish

SaltwaterFish

Scissortail dartfish (Ptereleotris evides)
Poco a poco · CC BY-SA 4.0

Care at a glance

Temperature
72–79°F
22–26°C
pH
8.1–8.4
Adult size
5.5 in
14 cm
Minimum tank
29 gal
110 L
Temperament
Peaceful
Social behavior
Social
Swim level
Middle
Diet
Carnivore
Difficulty
Easy
Breeding
Hard
Rarity
Common
Reef safe
Reef safe
Family
Ptereleotridae
Origin
Indo-Pacific, from the Red Sea and East Africa to the Line and Society Islands, north to the Ryukyu Islands and south to Lord Howe Island

Overview

The scissortail dartfish is a peaceful hovering fish for the middle of a reef tank. It is a good first fish for a reef.

Did you know

When startled, a scissortail dartfish does not bolt for the nearest rock like most fish. It drops straight down into its burrow in the sand, vanishing in a fraction of a second. Minutes later it eases cautiously back up.

Caring for the scissortail dartfish

Give scissortail dartfish a tank of 29 gal (110 L) or more. Add a few inches of sand for burrowing, with loose rubble or rockwork nearby. Leave open water for them to hover in. Jumping is their biggest risk in captivity, so a secure, tight-fitting lid is not optional.

Keep the water at 72 to 79°F (22 to 26°C) and a pH of 8.1 to 8.4. Feed a variety of small meaty foods such as mysis, brine shrimp and finely chopped seafood. They are constant, energetic feeders, so feed them a couple of times a day.

Scissortail dartfish are peaceful and reef safe, ignoring corals, clams and other invertebrates entirely. Keep them with other peaceful tank mates, never with boisterous fish that will bully them away from the open water they like to patrol.

They are social and do best in a group of three or more, which hovers together in a loose formation. A group behaves far more confidently than a single fish kept alone. Breeding them is hard.

Good to know

The scissortail dartfish belongs to the family Ptereleotridae and is also called the blackfin dartfish. Its body is two-toned, pale blue-gray up front and shading to black across the rear half and tail. The tall, forked tail gives it the scissortail name, since the two lobes open and close like blades as it swims. Unlike true gobies, it has no fused pelvic sucker, and it swims freely in open water rather than resting flat on the bottom.

In the wild

The scissortail dartfish ranges across the Indo-Pacific, from the Red Sea and East Africa to the Line and Society Islands. Its range runs north to the Ryukyu Islands and south to Lord Howe Island. It lives on outer reef slopes and in lagoons, at depths of about 2 to 15 meters. There it hovers just above a shared burrow system in sand or rubble.

Weekly picks

Tank mates

The scissortail dartfish is a peaceful, social species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a scissortail dartfish need?

A scissortail dartfish needs at least 29 gal (110 L). It spends most of its time in the middle.

What temperature and pH does a scissortail dartfish need?

A scissortail dartfish is comfortable at 72–79°F (22–26°C) with a pH of 8.1–8.4.

What does a scissortail dartfish eat?

A scissortail dartfish eats a variety of small meaty foods, such as mysis, brine shrimp and finely chopped seafood. It is a constant, energetic feeder, so feed it a couple of times a day.

How big does a scissortail dartfish get?

An adult scissortail dartfish reaches about 5.5 in (14 cm).

Related species