Zebra Dartfish (Ptereleotris zebra)
Also known as the Shotsilk Goby
• Small fish safe: ✅ Yes
• Small invert safe: ✅ Yes
• Coral safe: ✅ Yes
• Minimum tank size: 114 liters (30 gallons)
• Adult size: Up to 10 cm (4 inches)
• Diet: Carnivorous, primarily feeding on zooplankton
• Be aware of: Highly prone to jumping, requiring a secure lid; best kept in small groups; needs a peaceful environment to thrive
Appearance and Coloration
The Zebra Dartfish is a slender, elongated species with a silver to pale blue body accented by multiple thin, dark horizontal stripes running from the head to the tail. The stripes give it the “zebra” pattern for which it is named. Its long, flowing fins add to its elegant appearance, making it an attractive schooling fish for reef aquariums.
Natural Habitat and Behavior
Ptereleotris zebra is found throughout the Indo-Pacific region, commonly inhabiting sandy reef flats and lagoons at depths of 3 to 30 meters (10 to 100 feet). They are naturally social fish, forming small groups that hover near the sand bed, darting into burrows or crevices when threatened.
Unlike some goby species, they do not form symbiotic relationships with pistol shrimp but instead prefer hiding among rock formations or digging their own burrows in sandy substrates. They are shy at first but become more confident when housed with a small group of their own kind.
Tank Requirements and Water Parameters
• Minimum Tank Size: 30 gallons (114 liters) for a small group
• Water Parameters:
• Temperature: 24°C – 27°C (75°F – 81°F)
• pH: 8.1 – 8.4
• Specific Gravity: 1.020 – 1.025
• Aquascaping:
• Provide plenty of live rock caves and crevices for shelter.
• A fine sandy substrate is ideal, as they may dig burrows.
• Open swimming space is essential for their hovering behavior.
• Lighting: Moderate to bright, mimicking natural reef conditions.
• Water Movement: Moderate flow to replicate their natural environment.
• Tank Cover: A secure, tight-fitting lid is mandatory, as Zebra Dartfish are exceptionally prone to jumping, especially when startled.
Diet and Feeding
Zebra Dartfish are micro-carnivores, feeding primarily on zooplankton and small invertebrates in the wild.
• Natural Diet: Zooplankton and tiny marine invertebrates.
• Captive Diet:
• Mysis shrimp
• Brine shrimp
• Copepods
• Finely chopped seafood (fish, shrimp)
• High-quality marine flakes and pellets
Feeding Frequency: 2-3 times daily in small portions to support their high metabolism.
Compatibility and Social Structure
• Temperament:
• Very peaceful, making them ideal for community reef tanks.
• Best kept in pairs or small groups—they are naturally social and feel more secure in numbers.
• Tank Mates:
• Compatible with other peaceful fish, such as gobies, clownfish, wrasses, and chromis.
• Avoid aggressive or large predatory species that may harass or outcompete them for food.
• Reef Compatibility: 100% reef-safe—does not harm corals or invertebrates.
Important Considerations
• Jumping Behavior: One of the most prone-to-jumping species in the hobby; a secure lid is non-negotiable.
• Social Nature: More confident in small groups; keeping them alone may result in stress and excessive hiding.
• Shyness: Can be skittish when first introduced but will become bolder with time in a peaceful environment.