Minimum Tank Size: 20 Gallons (75 Litres)
Care Level: Moderately Hard
Water Conditions: 6.5 – 8.5 pH and Moderately Hard to Very Hard
Temperature: 66-86 °F (18-30 °C)
Maximum Size: 2 inches (5.5 cm)
The American flagfish (Cyprindon floridae), also known as the Florida flagfish – or simply the flagfish, is a small pupfish that is only sporadically available in fish stores. Which is a somewhat strange fact, since this is a hardy, unique looking fish, whose stripes closely resemble the American flag.
This fish is native to Florida, and is commonly found in slow moving, heavily vegetated waters, which include marshes, swamps, ponds, canals, and lakes.
It remains relatively small in the home aquarium, and most will grow to a maximum size of 2 inches (5.5 cm). Most American flagfish have a life span of around two to three years, though if they are exceptionally well cared for, they can live for as long as five years. There have even been some reports of them living for up to eight years, though this is very rare.
American flagfish are a hardy and undemanding fish, and a pair of them can live quite comfortably in a 20 gallon (75 litres) aquarium. While they are content to be kept in small groups, they tend to do better when kept in groups of six or more. If you are keeping them in larger groups, then the aquarium size should be upgraded accordingly.
Some people have reported success with keeping American flagfish in a community tank, but you have to choose their tankmates carefully. They tend to be aggressive fin nippers, and any fish kept with them should be narrow bodied, fast swimming fish.
The males tend to be quite territorial, and they require a fair bit of room to set up a territory in. However, in larger tanks, you can quite easily accommodate a handful of males without too many issues. To help disperse the aggression, the tank should include plenty of plants, driftwood and rocks, which will help to break the male’s line-of-sight. But be sure to leave an open area for swimming when setting up their aquarium.
To really bring out the flagfish’s colors, you should consider using a dark substrate. Gravel is an excellent choice for the substrate in an American flagfish’s tank, though a dark colored sand will also work just as well.
When choosing a filter for a tank containing American flagfish, it’s important to keep the current in the tank to a minimum. Probably the easiest way to keep the current down is to use an air powered sponge filter. This has the added benefit of making it safer for the fry, which often have a high mortality rate from other types of filters.
American flagfish are omnivores, and feed on crustaceans, algae, insects and plant matter in the wild. This diet should be recreated as closely as possible in the home aquarium. This can be accomplished through feeding them a high quality flake food, and regular feedings of vegetables. An excellent choice to feed them is Hikari Tropical Algae Wafers. Not only is it a high quality food, but it also helps provide them the algae they need in their diet.
They will also greedily accept any live or frozen foods that you can provide. Their favorite live foods are daphnia, brine shrimp and blackworms. If no live foods are available, then frozen daphnia, brine shrimp, bloodworms or blackworms can be offered on a semi-regular basis.
It’s very important that you regularly provide them with vegetables, especially if there isn’t much hair algae for them to feed on in their tank. Some of their favorite vegetables are blanched and shelled peas, and zucchini or cucumber medallions. Even with regular feedings of vegetables, you should still consider feeding them an algae based food several times a week.
The American flagfish is one of the easiest killifish to breed, and you can accomplish it without too much work on your part. They will often breed on their own in the spring and winter, though this seems to occur more during the spring and fall months.
Usually any fish are sexed prior to be added to the tank (mainly to prevent having a tank full of aggressive males). But if you need to sex the fish, the females are usually larger, with plumper bodies than the males. They also have a dark spot on the dorsal fin that males do not have and have more of a yellow coloration to their bodies.The males tend to be greener than the females, and as a rule are significantly more colorful than the females. Their dorsal-fin will also be larger as are their anal fins.
Many articles claim that American flagfish dig out pits, and show parental care to their eggs and young. I have never encountered this, and in my experience they appear to be egg scatterers. I can’t say if this is common across all American flagfish, but it has occurred with several separate pairs with me.
The males will set up territories, in which they will then entice the females into. Once the female has been enticed into the territory, the male will display to the female. If the display is successful, the female will swim away to a plant or other surface and the male will follow. The male will then attach himself to the female from below, and in quick jerking motions, the eggs will be released. This may be repeated several times before the fish are done.
The eggs are attached by a sticky thread to the surface, and while American flagfish parents don’t normally eat all of the eggs, many will still be lost if the parents aren’t removed. This is especially true in any aquarium that isn’t heavily planted. If you want to maximize the number of fry, the parents should be removed immediately after breeding.
The fry will hatch after 7-10 days, and they can be fed mircoworms or baby brine shrimp. They aren’t adept at swimming when they first hatch, and you will see the majority of the fry staying near the bottom on the tank. You should concentrate your feeding efforts towards the bottom, or the fry may miss the food.
One of the reasons that these fish are often sought after, is that they are one of the few fishes that consume hair algae. While they may not be perfect fit for every aquarium that is struggling with hair algae, it can be a great way to control it in some aquariums. A word of caution though – they are also known to eat plants, so be aware that they can damage carefully aquascaped aquariums.