Marble Hatchetfish

Appearance & Behavior

Marble Hatchetfish (Carnegiella strigata) bring intricate dark marbling and a distinctive, deep-chested silhouette to the surface of a freshwater aquarium. These small, peaceful schooling fish hover just beneath the waterline, waiting for tiny foods to drift within reach. A settled group adds quiet movement to the often-overlooked top level of a planted community tank.

Quick Care Guide

• Care Level: Moderate; best in a mature, stable aquarium
• Temperament: Peaceful and sometimes shy
• Adult Size: Approximately 1.5 inches
• Minimum Tank Size: 20 gallons, with a broad surface area
• Temperature: 75–82°F
• pH: 5.5–7.0
• Water Hardness: Soft water preferred
• Diet: Primarily carnivorous; small insects and other tiny invertebrates
• School Size: At least 6; larger groups are preferred when space allows
• Tank Level: Surface

Aquarium Setup & Compatibility

A tightly fitting lid is essential. Marble Hatchetfish are powerful jumpers and can escape through small openings, so cover gaps around filters, cords, and tubing. Provide floating plants or overhanging cover while leaving open surface space for swimming and feeding. Gentle water movement, subdued lighting, and a mature, well-filtered aquarium help them settle in.

Keep them with calm, similarly sized fish such as small tetras, rasboras, pencilfish, and peaceful Corydoras. Avoid aggressive fish, fin-nippers, and boisterous surface feeders that may frighten them or monopolize food. Maintain stable water conditions with regular partial water changes, and acclimate new arrivals carefully. These social fish should be kept in a group rather than alone.

Feeding

Offer tiny foods that remain at the surface, such as finely crushed tropical flakes, appropriately sized floating micro-pellets, and small live insects such as flightless fruit flies. Supplement with small live or frozen foods such as daphnia and baby brine shrimp, offering them near the surface. Newly arrived fish may respond best to live foods before gradually accepting prepared foods.

Feed small portions once or twice daily and watch to confirm every fish is eating. Marble Hatchetfish rarely search the bottom for food, so sinking leftovers are not a reliable food source for them.

Available for in-store pickup only.