Largescale four-eyed fish Care Guide: Diet, Tank Mates, Diseases, Breeding & More

Updated: December 17, 2022

The largescale four-eyed fish is a beautiful and unique freshwater fish that is native to South America.

This fish gets its name from the two large eyes on either side of its head, which help it see in both air and water.

The largescale four-eyed fish is a peaceful and hardy fish that is a great addition to any freshwater aquarium.

In this guide, we will go over everything you need to know about largescale four-eyed fish care. Tank size, diet, lifespan, and more!

Species overview

The largescale four-eyed fish (Anableps anableps) is a type of freshwater fish that’s native to parts of Central and South America. Their habitats tend to be brackish or saltwater marshes, mangrove swamps, and lagoons.

They get their name from the fact that they have two eyes on each side of their head, which gives them a very wide field of vision. This is an adaptation that helps them survive in their murky and often dangerous habitats.

Largescale four-eyed fish are very popular in the aquarium trade due to their unique appearance and interesting behavior. They are a hardy species that can adapt to a wide range of water conditions, which makes them a good choice for beginner fishkeepers.


Largescale four-eyed fish

The first thing you’ll notice about this fish is their unique eyes. As you can probably guess from their name, they have two large eyes on each side of their head. These eyes are very close together and sit just above their mouths.

The eyes of the largescale four-eyed fish are what give them their unique appearance

The rest of their body is long, thin, and eel-like. They have a dorsal fin that starts a little bit before their halfway point and extends the rest of the way back.

This dorsal fin is tall and slightly curved. The anal fin is much shorter and also curves slightly. Both of these fins have a dark outlining.

The caudal fin of this fish is forked and symmetrical. It’s also fairly tall, but not as tall as the dorsal fin.

The largescale four-eyed fish is a bottom-dweller, so their ventral fins are very prominent. These fins are long and thin and help the fish move along the substrate.

The coloration of this fish can vary quite a bit. They can be brown, green, yellow, or a mix of these colors. There is usually a dark stripe that runs along the middle of their body from head to tail.


The largescale four-eyed fish is a long-lived species with a lifespan of up to 20 years. This fish is not suitable for the home aquarium as it grows too large and is a skilled escape artist. It is best suited for large public aquariums.


The largescale four-eyed fish is a small aquarium fish that only grows to be about 3 inches in length.


Tank Size

The minimum tank size for a largescale four-eyed fish is 40 gallons. This fish is a little on the large side and will need plenty of space to swim and explore. If you have a smaller tank you may be able to keep one but it’s not recommended.

In addition to being a large fish, the largescale four-eyed fish is also an active swimmer. It’s not a fish that likes to sit in one spot all day long.

You need to provide them with plenty of space to move around and explore. A 40 gallon tank is the bare minimum but we recommend going up to a 55 gallon tank if you can.

Water Parameters

The largescale four-eyed fish is a tropical fish that needs warm water to thrive. They’re native to slow-moving streams and rivers in Southeast Asia.

To keep your largescale four-eyed fish healthy, you’ll need to maintain the following water parameters.

  • Water Temperature: 75°F to 86°F
  • pH Levels: 6.0 to 7.5
  • Water Hardness: Soft to Moderately Hard
  • Alkalinity Levels: 2-12 dKH

What To Put In Their Tank

When it comes to setting up the inside of an aquarium for a Largescale Four-eyed Fish you can be as creative as you want. There aren’t any specific things that this species NEEDS to have, which gives you plenty of options.

We recommend some of the standard decorations that you find in a lot of freshwater tanks. There are a ton of great plants you can include (like hornwort or water wisteria). You can even throw in some floating aquarium plants too!

Rocks, driftwood, and caves are all suitable as well. It’s important to avoid going overboard with this since these fish like some room to swim.

Also, if you’re keeping your Largescale Four-eyed Fish in a smaller tank then it’s going to be difficult to include a lot of this stuff anyway.

A classic gravel substrate is always a good choice, but you can do with something soft and sandy if needed too (use other species you keep as a guide with this).

Common Diseases

Largescale four-eyed fish are a hardy species that is not often affected by disease. However, there are a few potential illnesses that you should be aware of.

The most common disease that these fish experience is ich. Ich is a very common freshwater parasite that can become quite serious if it’s not dealt with.

The most obvious sign of this disease is the series of white spots that will begin to cover the body of your fish.

There are plenty of other potential diseases that can affect this species as well, but they’re not as common.

Another thing to look out for is infection from cuts. The most common cause of this is keeping your Largescale four-eyed fish in a tank with a rough substrate (or aggressive species that want to fight).

In general, the best way to prevent these fish from getting sick is to maintain the quality of the water in their tank. A tank with clean and stable water conditions always leads to healthier fish who are more resistant to disease.

Behavior & Temperament

The largescale four-eyed fish is known to be a peaceful creature that can get along with other fish in the tank. They are not known to be aggressive and will usually leave other fish alone. These fish are also known to be good scavengers and will help keep the tank clean.

The largescale four-eyed fish is a nocturnal fish, so it will be most active at night. During the day, it will usually stay hidden among the plants or other décor in the tank.

One thing to keep in mind is that the largescale four-eyed fish is a jumper. They have been known to jump out of tanks, so it is important to make sure that your tank is covered.

Tank Mates

Largescale four-eyed fish are best kept as a species-only tank. They’re not the friendliest of fish and can be quite aggressive.

Males are especially territorial and will fight with one another if they’re not given enough space.

Since these fish come from fast-moving waters in the wild, they prefer to have a tank with plenty of space to swim. A long and narrow tank is ideal since it gives them more of a horizontal plane to swim on.

As for other tank mates, the only species that can really hold their own are other large, aggressive fish. Even then, it’s best to err on the side of caution and avoid mixing them.

Some potential tank mates include:


Largescale four-eyed fishes are great parents and will take care of their young if given the chance. If you’re looking to breed these fish, the process is fairly simple and doesn’t require much intervention.

Start by setting up a breeding tank. It should be at least 30 gallons and have a fine layer of gravel on the bottom. The water should be clean and well-filtered. Aim for a temperature between 77 and 86 degrees Fahrenheit.

Then, add some hiding places. These fish like to have places to retreat to, so add caves, plants, and other decorations.

Once the tank is set up, add two males for every female. You can sex them by looking for the white spots on the males’ gill covers.

Feed the fish plenty of high-quality foods. Then, begin changing about 50 percent of the water. That should trigger spawning.

The female will lay her eggs in a cave or other hiding place. Once she does that, the male will guard them diligently. He’ll also fan them with his fins to keep them oxygenated.

In about ten days, the eggs will hatch. You can move the babies into a nursery tank to improve their odds of survival. Feed them live foods and small bits of meaty foods.


The Largescale Four-eyed Fish is a great fish for beginners and experienced aquarists alike. They’re easy to care for and make a great addition to any community tank.

Their unique appearance is sure to turn heads, and their calm nature means they won’t cause any problems in your tank.

If you’re looking for a new fish to add to your collection, we highly recommend the Largescale Four-eyed Fish!