Lined Dart Grammica (Ptereleotris Grammica) saltwater aquarium fish portrait

Ptereleotris grammica is one of the more striking members of the dartfish group, built along slender, elongated lines and finished in iridescent blue over a yellowish to tan base. Sparkling gold and blue-purple stripes run the length of the body, and the fins carry a distinctive shape, with enlarged pelvic fins the fish uses to anchor itself at the mouth of a burrow. The species ranges widely through the Indo-Pacific, from Indonesia and the Philippines into Micronesia and across the tropical Western and Central Pacific and Indian Ocean, where it occupies coral reef slopes and the transition zones where rock and rubble meet open sand. Most specimens are collected between roughly 5 and 50 meters, and some come from water deeper than 100 feet.

Adult housing begins at 30 gallons, and a pair settles comfortably into a 30- to 40-gallon aquarium. Aquascape with generous loose coral rubble and rockwork that creates numerous retreats, and finish the bottom with a mixed-grain sand bed for occasional burrowing. These fish do not excavate their own tunnels; they commandeer burrows dug by other fish or invertebrates, so ready-made shelter matters more than substrate depth. Leave ample open water above the rock, since much of the day is spent hovering in the current. Moderate to strong flow in the range of ten to twenty times total tank volume suits them well.

A tight-fitting, fully covered lid is not optional. This species is a prolific jumper that bolts into any available gap when startled, including straight up, and an open-top system will eventually cost you the fish. Close any overflow, return, and feeding gaps as carefully as the main opening.

On the reef, the Lined Dartfish feeds as a planktivorous carnivore, picking small organisms from the water column above its burrow. In the aquarium, offer a varied meaty menu built around mysis shrimp, brine shrimp, live copepods, rotifers, quality frozen plankton blends, and finely chopped or shaved seafood such as prawn and mussel. Over time, most individuals will also take a high-quality sinking pellet.

Feed at least twice daily, and more frequently when possible, because constant hovering burns considerable energy. Newly added specimens are often shy about feeding, so several small offerings spread through the day give a timid fish repeated opportunities to eat. Presenting food right as the lights come on, or as they go off with a nightlight in place, can encourage a reluctant new arrival to begin feeding in the open.

Mysis Shrimp Brine Shrimp Live Copepods Rotifers Frozen Plankton Blends Chopped Seafood Sinking Pellets
This is a peaceful and notably timid fish that spends its time hovering above the substrate, retreating into rockwork or a borrowed burrow at the first sign of disturbance. Pairs consisting of a male and female tend to do best, though individuals and small groups are also workable, and keeping them alongside other dartfish species often makes the whole group bolder. Juveniles congregate in large aggregations in the wild, while adults are usually encountered singly or in pairs.

Tankmate selection is the single biggest factor in long-term success. Larger, aggressive, or hyperactive fish intimidate this species into permanent hiding, which quickly leads to poor feeding and eventual starvation. Pair it with other dartfish, cardinalfish, dragonets, small peaceful clownfish, fairy wrasses, and gobies, and use caution with chromis, small anthias, hawkfish, and blennies. Avoid groupers, eels, and other large predators entirely. The species is reef safe, posing no threat to corals or other sessile invertebrates, and it occupies burrows made by creatures such as pistol shrimp without harming them, though it does not form a true symbiotic partnership.

FAQ

Frequently Asked Questions

About the Lined Dart Grammica

  • What size tank does a Lined Dartfish need?
    A minimum of 30 gallons is recommended, and a pair does well in a 30- to 40-gallon aquarium with rubble and rockwork, a sand bed, and a securely covered top.
  • Is the Lined Dartfish reef safe?
    Yes. It does not harm corals or other sessile invertebrates, though it may take over a burrow dug by another animal such as a pistol shrimp without forming a true symbiotic relationship.
  • Why does this species need a covered aquarium?
    Lined Dartfish are prolific jumpers that dart into any opening when startled, including upward. A tight-fitting lid with all gaps sealed is essential.