Maximum size : 7 cm

American Flagfish - Jordanella floridae : Complete Fish Profile & Care Guide

Table of contents


American Flagfish (Jordanella floridae) are captivating species with their striking appearance and engaging behaviour. These fish have earned their place as a favoured choice among aquarists. This resilient and adaptable fish species has become a notable addition to many home aquariums. American Flagfish are ideally kept as solitary specimens, particularly if the goal is to encourage breeding behaviour. However, with careful research and consideration, they can coexist within a well-planned community aquarium, provided there is ample space to accommodate their specific requirements. When selecting tankmates, it is advisable to choose species that share a similar size and temperament while also thriving in the same cooler, slightly alkaline environmental conditions.

To ensure the well-being of American Flagfish in an aquarium setting, it is advisable to establish a mature environment replete with dense plantings, including robust or fast-growing species. Utilizing a dark-coloured substrate not only promotes a sense of security among the fish but also serves as an ideal backdrop to accentuate the vibrant hues of mature male specimens. The inclusion of a floating cover to diffuse the lighting will be beneficial for these fish. Given their omnivorous nature, delicate soft-leaved plants may be susceptible to grazing. Adequate filtration is essential, coupled with gentle water movement, to replicate their natural habitat conditions. American Flagfish typically exhibit a peaceful demeanour outside of their spawning periods. Therefore, providing a spacious aquarium with ample hiding places can help mitigate potential conflicts during these times. Any aggression usually tends to be directed toward conspecifics. However, with sufficient space and well-placed visual barriers within the decor and plantings, such issues can be effectively managed.

These small, hardy, and robust fish sport a distinctive lopped snout, often compared to a bulldog's. Their rounded fins, positioned posteriorly and adjoining the caudal fin, are adorned with slight reddish hues that can come and go. Females feature a prominent spot on their flanks and a transparent spot near the posterior end of the dorsal fin, bordered by an opaque white margin. During the breeding season, the male's appearance is striking, resembling the stars and stripes of the United States flag, with a dark spot positioned at the lower rear corner of the dark rectangle. Their body is mainly olive, accented with turquoise scales, adding a dazzling effect to your aquarium.

American Flagfish Photos

Sexual Dimorphism

Distinguishing between male and female American Flagfish is a straightforward task. Adult males exhibit extended anal and dorsal fins, showcasing a strikingly colourful appearance, particularly when in spawning conditions. On the other hand, adult females have a rounder belly than males, especially when gravid, and feature a dark blotch on the posterior part of the dorsal fin, absent in males.

Featured Male
Featured Female
Female Male

Quick Facts

Scientific NameJordanella floridae
Year Described1879
Other NamesFlagfish, Florida Flagfish
OriginsUnited States
Max Size7 cm
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asTrios
Diet & FeedingOmnivore
ReproductionEgg Depositor
LifespanUp to 5 Years

Water Parameters

Water TypeFreshwater
pH 6.5 - 8.5
GH 5 - 20
TDS 36 - 357
Ideal Temperature
64 - 86
17 - 30

Natural Habitat

The American Flagfish is found exclusively in Peninsular Florida, south of the Ochlockonee and St. Johns River Basins in the United States. Inhabiting a range of waterbodies, including shallow, heavily vegetated still to slow-moving freshwaters like ponds, lakes, backwaters, floodplains, marshes, canals, ditches, and streams, these specimens are known to adapt to their surroundings. While they primarily reside in freshwater, they have been observed in slightly brackish water, making for a fascinating sight. Their natural habitat is diverse and abundant, offering aquarists a glimpse into the mesmerizing world of aquatic ecosystems.


American Flagfish exhibit fractional spawning behaviour, where females release eggs intermittently over an extended period when warm temperatures are sustained. Nonetheless, allowing them to breed seasonally in the spring and late summer is advisable, as they would in their natural habitat. The males will form temporary territories in which they will defend against rivals while attempting to lure females into spawning; dominant individuals will display more intense colouration. 

The eggs will be released singly or in small batches and attached to algae or other surfaces using tiny threads. Neither males nor females show parental care towards their eggs once they have been deposited. While some eggs may get eaten if left with the parents, this species isn't incredibly insatiable. The fry will appear in with the adults if plenty of plant cover is present. However, the most productive method is to remove the eggs and hatch them in a separate grow-out tank containing water of the same temperature and chemistry as that of the adults.

The incubation period is temperature-dependent, although generally, it takes between 7 to 14 days. You should initially offer the fry green water or infusoria, moving on to microworm and artemia nauplii when they become free-swimming. Unfortunately, the larger-sized babies will not hesitate to eat their smaller siblings, so it would be better if you separated the fry by size if some grow more quickly than others.

Diet & feeding

American Flagfish predominantly graze on available algae in the aquarium. However, if the algae supply is insufficient, supplement their diet with high-quality dried foods such as flakes, pellets, or algae wafers, as well as live and frozen options such as brine shrimp, white worms, tubifex, daphnia, and bloodworms. Additionally, providing them with occasional treats of blanched vegetables like zucchini or spinach would be beneficial to their nutrition. A well-rounded diet is critical to promoting their overall health and vitality, and aquarists should take care to provide a balanced selection of foods to ensure their American Flagfish thrive in the aquarium.

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