Banded Killifish

The Banded Killifish inhabits quiet bays, ponds, and slow-moving streams of eastern North America from the Atlantic coast to the Great Lakes. It is a surface-oriented species that feeds on insects, small crustaceans, and plant matter falling onto the water surface.

In the aquarium it is active and relatively peaceful, schooling loosely in the upper water column. The species appreciates surface plants such as water sprite or frogbit under which it shelters and spawns. Males develop brighter silver banding during the breeding season.

Fundulus diaphanus is one of the hardiest North American killifish, tolerating temperatures from near freezing to the low twenties Celsius, making it an excellent candidate for unheated aquariums.

Water: 8–22°C, pH 6.5–8.0, GH 5–18; very cold-tolerant; no heater required in temperate climates. Tank: minimum 80 L with surface plants (water sprite, frogbit); tight lid as they jump readily. Feeding: omnivore — flake, floating pellets, frozen daphnia, cyclops, and brine shrimp. Breeding: deposits adhesive eggs on fine-leaved plants near the surface; non-guarding; eggs hatch in 10–14 days. Compatibility: peaceful; schools loosely with own species; avoid tiny nano fish that may be eaten.