Tropical Gar Care Guide: Diet, Tank Mates, Diseases, Breeding & More

Updated: December 1, 2022

The tropical gar is an absolutely stunning fish that is perfect for the freshwater aquarium.

These fish have a very unique appearance with their long bodies and needle-like teeth. They’re also very active swimmers and make a great addition to any community tank.

But before you go out and buy one, there are a few things you need to know about tropical gar care. In this guide, we’ll teach you everything you need to know about keeping these fish happy and healthy.

Species overview

Tropical Gar (scientific name: Atractosteus tropicus) are found in tropical freshwater habitats in Central and South America. The majority of these fish are found in the Amazon Basin, but they can also be found in smaller numbers in the Orinoco Basin.

They prefer habitats with little to no current and a lot of vegetation. This is because they are ambush predators and prefer to lie in wait for their prey.

Tropical Gar are some of the largest freshwater fish in the world and can grow to be over six feet long! They are also one of the most dangerous fish in the world and have been known to attack and kill humans.

Despite their size and potential danger, Tropical Gar are a popular choice for freshwater aquariums. This is because they are such unique and impressive-looking fish.


Tropical Gar

The first thing you’ll notice about this freshwater fish is their unique shape. These fish have a very long and thin body that’s been described as eel-like by many aquarists.

Their bodies are covered in large scales that give them a bit of armor. These scales are diamond-shaped and have a rough texture. The majority of their body is a dark gray with a bit of a greenish tint.

The underside of these fish is a light gray or white. This color extends up their sides in a V-shape and continues until it meets the black stripe that runs along their dorsal fin.

This black stripe is quite thin and extends from the tip of their nose all the way to the end of their caudal fin.

Tropical Gars have a long and thin mouth that’s filled with sharp teeth. They have small eyes that are set far back on their head.

Their dorsal fin is tall and starts about halfway back on their body. This fin is continuous and doesn’t have any rays sticking out.

Their caudal fin is forked and their anal fin is rather small. They have two small pectoral fins that are located just behind their gills.


The average lifespan of a tropical gar is 15 to 20 years. This is quite a long time for a fish, and is a testament to their hardiness. Of course, their lifespan can be affected by a number of different factors.

As with any fish, the quality of their environment has a big impact on how long they live. If the water is too cold or too hot, has the wrong pH, or is otherwise unsuitable, their lifespan will be shortened.

Stress is also a major factor. If they’re constantly being harassed by other fish or don’t have enough hiding places, their lifespan will be lower.


The average size of a Tropical Gar is around 24 inches, but they can grow to be up to 36 inches long. These are some of the larger freshwater fish, so you’ll need a pretty big tank to accommodate them. They can live in smaller tanks when they’re young, but they’ll need to be moved to a larger one as they grow.


Tank Size

The minimum tank size for a single gar is 180 gallons. If you want to keep more than one gar, you’ll need an additional tank for each fish.

Gars are large, active fish that need a lot of space to swim and explore. They’re also predators, so they need enough space to hunt for food.

Water Parameters

The tropical gar is a freshwater fish, so the water parameters you need to maintain are pretty standard. As with any fish, it’s important to be consistent with these parameters. That means no sudden changes that could stress the fish out.

The good news is that tropical gar are very adaptable fish. They can tolerate a wide range of water conditions, which gives you some wiggle room. Just remember that the closer you can stick to their natural habitat, the better.

Here are some basic water parameters to help create a healthy environment for your tropical gar.

  • Water Temperature: 72 to 82 degrees Fahrenheit
  • pH Levels: 6.0 to 8.0
  • Water Hardness: 4 to 20 dGH
  • Alkalinity Levels: 3 to 10 dKH

What To Put In Their Tank

The inside of a tropical gar’s tank doesn’t need to be too complex. A few pieces of driftwood and some plants are really all you need.

As for the plants, we recommend something that can withstand a fair amount of abuse. These fish are known to uproot plants as they’re swimming around, so something that can bounce back is ideal.

Java Fern and Anubias are both great choices. You could also go with something like Hornwort or Water Wisteria if you wanted to add a bit more color to the tank.

The substrate is another important consideration. These fish like to sift through the substrate looking for food, so you’ll want something that won’t be too harsh on their gills.

A soft, sandy substrate is ideal. If you can’t find sand then a gravel substrate will work too. Just avoid anything too sharp or jagged.

Common Diseases

The tropical gar is a hardy fish that can withstand a wide range of water conditions. However, this doesn’t mean that they don’t ever get sick.

There are a few diseases that these fish are particularly susceptible to. The most common is gill flukes, which are parasites that attach themselves to the gills of the fish and cause irritation.

If left untreated, gill flukes can eventually kill the fish. Another common disease is columnaris, which is an infection that attacks the skin and fins of the fish.

This can be caused by poor water quality, and it can eventually lead to the death of the fish if it’s not treated.

The best way to prevent these diseases is to maintain good water quality in the tank. This means regular water changes, filtering the water, and keeping an eye on the ammonia and nitrite levels.

If you notice any strange behavior or changes in the appearance of your fish, it’s always best to consult a vet or experienced fish keeper so you can get a diagnosis and begin treatment as soon as possible.

Behavior & Temperament

Tropical gar are one of the most aggressive freshwater fish. They are not afraid to attack other fish, and they will even eat smaller fish whole.

This fish is not for the faint of heart, and it is not recommended for beginners. If you are considering keeping a tropical gar, be sure to do your research and be prepared for a challenge.

Tank Mates

Tropical Gar are one of the most difficult fish to keep. They’re very sensitive to water conditions and need a lot of space.

For these reasons, it’s best to keep them alone. If you must have tank mates, choose species that are much smaller and can tolerate the same water conditions.

Some good choices include:

  • Neon Tetras
  • Ghost Shrimp
  • Guppies
  • Platies
  • Mollies


Breeding tropical gars is not for the faint of heart. It’s a difficult and dangerous process that should only be attempted by experienced fishkeepers.

Tropical gars are huge, reaching lengths of up to six feet. They’re also extremely aggressive. For these reasons, you must take extra care when breeding them.

The first step is to set up a breeding tank. It should be at least 300 gallons and well-filtered. The water should be clean and well-oxygenated. Aim for a pH of 7.0 and a temperature of 82 degrees Fahrenheit.

You’ll need to add a lot of hiding places to the tank. That way, the female can escape the male when she’s ready to lay her eggs. Caves, rocks, and driftwood all work well.

When the tank is ready, add one male and two or three females. The female will lay her eggs in a hidden area of the tank. The male will then fertilize them.

Once the eggs are fertilized, the male will guard them. He’ll also fan them with his fins to keep them oxygenated.

The eggs will hatch in about two weeks. At that point, you can remove the adults and raise the fry in a separate tank. Feed them live foods like baby brine shrimp.


Overall, we think the Tropical Gar is a great fish for experienced aquarists. They’re not the easiest fish to take care of, but they’re certainly not the hardest.

They’re also a lot of fun to watch and are very unique-looking fish. If you’re looking for something a little different for your tank, the Tropical Gar is a great option.

Just be sure to do your research before getting one and be prepared for a bit of a challenge.