Flagfish – Habitat, Feeding, Breeding, Tank Size & Mates

Disclosure: I may earn a commission when you purchase through my affiliate links. As an Amazon Associate I earn from qualifying purchases. – read more

This eye-catchy species often called as the American Flagfish (Jordanella Floridae) is sought after by many fish keepers who want to add something special to their collection. Although it is not the type of fish that you can find in any pet shop, it is definitely worth the effort to find one.

The Flagfish absolutely loves abundantly planted tanks where they can appear from the background and flourish in front of their viewers. It allows you to get creative and set up a decorative aquarium where this fish is going to be the cherry on top.

What makes this fish so amazing is the mix of metallic scales and colorful streaks that cover its body. It is going to stand out like a shiny jewel in front of all the plants, substrate and wood accessories.

Watching how the natural light reflects on its body in many different colors is going to be a mesmerizing experience.

Flagfish Natural Habitat

The scientific name for this beauty is Jordanella Floridae. As its name indicates, this species can be found in the ponds, canals and swamps of Florida.

There, both freshwater and brackish environments are ideal for them. Since it is used to still or rather slow-flowing water, the same should be mimicked in a home aquarium as well.

It can be said that the American Flagfish are cold water species, yet you shouldn’t shy away from keeping them together with tropical fish. However, it has to be noted that they prefer the lower temperatures in that category.

In their natural habitat, they hunt for worms, crustaceans and insects while eating plants from time to time. All in all, they are quite hardy fish that can be easily handled in home aquariums.

Flagfish Aquarium Requirements

Flagfish Aquarium Requirements (source)

This fish can be kept in aquariums and ponds as well. We would recommend you the former option since that provides a better way for showcasing their amazing colors.

Your fish tank should be well-planted with various greenery. In order to stop your fish from nipping on plants, make sure to feed them enough plant-based foods and mostly algae.

Placing them in a community aquarium is the best thing you can do. They won’t get aggressive if there is enough free space for them to swim around and shadowy areas provided by plants, wood or rocks.

If there is not enough space, on the other hand, then they get territorial and that’s not something you want to see in a community aquarium. The tank should be 15 to 20 gallons of size, which will make sure that other fish won’t bother the Flagfish to the point where he gets territorial.

Buying gravel that has a darker shade allows your fish to truly show its colors in the tank. Fish shops sometimes even sell black gravel, which might be more expensive but also makes your aquarium more decorative.

Flagfish Water Conditions

Now the American Flagfish is one of the hardiest aquarium fish you can get. It can adapt to various water conditions and environments. Therefore, we can lightheartedly recommend this unique species to beginner fish keepers.

Make sure that the water flow generated by filters is as low as possible. They can get stressed out if it gets too strong.

When it comes to water acidity, it should be kept between 6.5 and 8.5 pH. Since Flagfish are hardy fish, the temperature range is quite wide, allowing you to set it anywhere between 64-85 degrees Fahrenheit.

Ideal water temperature and cleaning can be ensured just by installing an adjustable heater and a sponge filter. Sponge filters not only lock down various beneficial bacteria but they are also straightforward to clean and use again.

One way to change the water throughout the week is to use it for watering your plants in the house. This way, you are frequently removing small amounts every day which can be replaced with fresh water each time.

Either way, periodic water replacement is very important for the American Flagfish.

Flagfish Diet & Feeding Schedule

The American Flagfish is one of those species that is going to eat almost anything in the aquarium. Hair algae is definitely among its favorites. When there are barely any algae left in the tank, you should buy some algae-based fish food in the shop. Algae wafers, for example, are widely used for this purpose.

Otherwise, they are going to start to eat parts of the plants they can find in the tank. Besides that, they are going to eat insects, crustaceans and worms or any commercial fish food that contains anything like that. When it comes to eating, they are rather bottom dwellers since that’s where they mostly like to consume their food.

We can conclude that they prefer to eat plant-based foods and they are definitely not going to eat other fish. If you want to add some variety to their diet, you can always get some freeze-dried brine shrimp, blackworms or bloodworms. They are going to be more than happy to eat those too.

If you notice that algae rapidly started to grow in your aquarium, then the best tactic is to give them very low amounts of food. This way, they are only going to feed on algae until the tank becomes completely clean. Then you can continue giving them regular amounts.

Flagfish Tank Mates

Now since the American Flagfish has a specific personality, you need to be a bit careful when setting up your community tank. The point here is to avoid putting them together with particularly slow and passive fish. Living together with those types only causes them to become hyperactive, which will lead to frequent fin nipping.

Therefore, bettas and guppies should be definitely avoided. You should opt for some more energetic fish such as tetras or danios. If you insist on keeping them with the above mentioned passive fish, then you will need at least a 20-gallon tank.

The other thing you will need to do is to use plants, rocks, wood pieces and other accessories to break the line of sight of your Flagfish.

This way, they won’t be compelled to bully the other fish in the tank. Meanwhile, they can peacefully swim around and recharge until they meet up with their Flagfish friends again. We would recommend you to get some Neon Tetras or Rummy Nose Tetras.

These not only look amazing but also get along well with the American Flagfish. You can even use the Rummy Nose Tetra as an indicator. If it flourishes in a vivid red color, then it means that the tank conditions are ideal.

As a result, you will end up with a very interesting and fascinating community tank that you will be proud to show to your friends.

Flagfish Breeding

Flagfish Male and Female – Breeding (source)

You can easily distinguish males from females just by looking at their anal and dorsal fins. Males not only have bigger fins but they flourish in more vivid colors as well. Females, on the other hand, have a noticeable dark spot on their dorsal fin. The breeding process is not complicated at all, but it can only happen in the right conditions.

The difficult part is to keep the fry alive in a community tank but you can always do that in a separate one. In fact, it is best to set up a complete breeding tank for your Flagfish. The optimal temperature for breeding is somewhere around 72 degrees Fahrenheit. The point is to set it to be slightly higher than normal.

There should be hiding places where the female can retreat in case the male gets too pushy. When you set up this tank, you need to think about the fry as well. Install a soft sponge filter and buy some fine substrate because the fry can get stuck in the big-grained ones.

The breeding itself starts with an enticing dance. After that, the female lays her eggs either in the roots of plants or down in the substrate. Then let the male guard those eggs until the eggs hatch. Once the fry are out swimming, remove the male to a separate tank.

Now the fry have to complete the development of their swim bladder right after they start swimming. This means that they have to reach the surface after hatching, otherwise they die. They can do this only if the water is shallow enough so that they don’t need to swim that much.


Keeping American Flagfish in your aquarium is a great way to add some shine and color to it. You are going to be pleased with the view of this unique metallic fish after you let it in the tank. This is one of those decorative fish that are not sensitive to the water conditions at all.

They don’t require a specific diet either. If this is the first fish you are about to keep at home, then we can only encourage you to do so. Since there are not many things that can go wrong, you will be able to keep them healthy and thriving with little effort.

It is best to start by keeping only Flagfish and then slowly add other fish to the tank as you gain more experience.

People usually keep Goldfish outside in their ponds but the American Flagfish is another outstanding alternative. With the mix of these two fish, you can create an eye-catchy attraction for your yard. Either you keep them in an aquarium or in a pond, there should be plenty of plants around them.

We hope that this article encouraged you to set up a neat fish tank and get your first Flagfish!

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.
Leave a Comment

Your email address will not be published. Required fields are marked *