Scissortail Dartfish (Ptereleotris evides)

 

• Small fish safe: ✅ Yes

• Small invert safe: ✅ Yes

• Coral safe: ✅ Yes

• Minimum tank size: 114 liters (30 gallons)

• Adult size: Up to 14 cm (5.5 inches)

• Diet: Carnivorous, primarily feeding on zooplankton

• Be aware of: Extremely prone to jumping, requiring a secure lid; best kept in pairs or small groups; shy and requires peaceful tank mates

 

Appearance and Coloration

The Scissortail Dartfish is an elegant and streamlined species, with a silvery-gray to bluish-white body that fades into a deep black tail. It has an elongated shape and a distinctive deeply forked caudal fin, giving it the appearance of a pair of scissors—hence its common name.

This species exhibits graceful hovering behaviour, spending much of its time in open water near the substrate, making it a visually appealing addition to a peaceful reef tank.

 

Natural Habitat and Behavior

Ptereleotris evides is found in tropical reefs across the Indo-Pacific, commonly inhabiting sand flats and reef slopes at depths of 3 to 40 meters (10 to 130 feet). They are typically seen in loose groups, hovering near burrows in the sand, which they retreat into when threatened.

They are shy but social fish, preferring to live in pairs or small groups. When kept singly, they can be more prone to stress and may spend extended periods hiding.

 

Tank Requirements and Water Parameters

• Minimum Tank Size: 30 gallons (114 liters) for a single fish, 50+ gallons for pairs or groups.

• Water Parameters:

• Temperature: 24°C – 27°C (75°F – 81°F)

• pH: 8.1 – 8.4

• Specific Gravity: 1.020 – 1.025

• Aquascaping:

• Soft sand substrate to accommodate their burrowing tendencies.

• Live rock structures with caves and overhangs for retreat.

• Open swimming space is essential for their hovering behavior.

• Lighting: Moderate to bright, as they are naturally found in well-lit reef areas.

• Water Movement: Moderate to strong flow, simulating their natural reef environment.

• Tank Cover: A secure lid is mandatory, as this species is an extreme jumper and can easily escape through even the smallest gaps.

 

Diet and Feeding

Scissortail Dartfish are micro-carnivores, feeding primarily on zooplankton and tiny crustaceans in the wild.

• Natural Diet: Zooplankton and small invertebrates.

• Captive Diet:

• Mysis shrimp

• Brine shrimp

• Copepods

• Finely chopped seafood (fish, shrimp)

• High-quality marine flakes and pellets

Feed small portions 2-3 times per day to keep them active and well-fed.

 

Compatibility and Social Structure

• Temperament:

• Extremely peaceful, making them ideal for community reef tanks.

• Best kept in pairs or small groups—they thrive in social settings.

• When housed alone, they can become more reclusive and stressed.

• Tank Mates:

• Compatible with other peaceful species, including gobies, clownfish, and wrasses.

• Avoid aggressive tank mates like dottybacks, large angelfish, or triggerfish.

• Reef Compatibility: 100% reef-safe—does not harm corals or invertebrates.

 

Important Considerations

• Jumping Behavior: This species is extremely prone to jumping and requires a securely covered aquarium.

• Shy at First: May take time to adjust but becomes more confident when housed in pairs or groups.

• Tank Stability: Prefers mature aquariums with stable water conditions.