Killifish - American Flagfish

The American flagfish (Jordanella floridae) is a small, hardy killifish native to Florida, highly valued in the aquarium hobby for its vibrant "stars and stripes" coloration and voracious appetite for nuisance hair algae.

Key Species Overview

• Scientific Name: Jordanella floridae
• Common Names: American flagfish, Florida flagfish, flag pupfish
• Origin: Endemic to Florida, commonly found in heavily vegetated lakes, swamps, and sluggish streams.
• Size: Reaches a maximum adult length of about 5.0 to 6.5 cm (2 to 2.5 inches).

Aquarium Care Requirements

• Tank Size: Minimum of 10 to 20 gallons to accommodate their active nature.
• Temperature: 18°C to 30°C (64°F to 86°F). They adapt very well to unheated aquariums.
• Water Parameters: pH of 6.5–8.5; generally adaptable to soft or hard water.
• Diet: Omnivorous. Highly prized for cleaning up filamentous algae and uneaten flakes; supplement with high-quality flakes, brine shrimp, and occasional blanched vegetables.
• Tank Mates: Best kept in a community tank with robust, non-long-finned fish. They can sometimes be nippy or territorial, especially during breeding.

Sexual Dimorphism

• Males: Highly vibrant with alternating rows of shimmering green/blue and red horizontal stripes. They feature a prominent dark blotch on their flank and are generally slightly larger.
• Females: More olive-brown with muted colors. Both sexes have a dark spot on their side, but females specifically possess an additional dark ocellus (eyespot) on their dorsal fin.