Skip to Content

Can Oscar Fish Live With Turtles? (With 6 Possible Alternatives)

Disclosure: When you purchase something through my affiliate links, I earn a small commission. As an Amazon Associate, I earn from qualifying purchases.

As a fish owner who loves Oscar fish, there was a time when I considered introducing turtles to their tank. However, I knew that Oscars are quite aggressive. Since turtles are quite expensive, I didn’t want to take my chances. That was when I began to research whether or not Oscars and turtles can get along.

Oscar fish and turtles can live together in the same tank, since both species require similar water conditions, such as temperature and pH. However, Oscars may eat small turtles and vice versa. That is because both species are relatively aggressive and will take advantage of easy prey.

However, as we move forward, I will show you in which cases Oscar fish and turtles can live in the same tank (followed by Youtube videos). I will also share a few essential steps you should take to make the coexistence more likely to happen.

Also Read: 19 Great Oscar Fish Tank Mates

Oscar Fish and Turtles: Can They Live Together?

Turtles are such fascinating creatures that people are always contemplating the notion of pairing them with aquarium fish. Is it a good idea? Can turtles and fish coexist in the same tank? The answer to that question will vary depending on various factors and conditions.

Can turtles live with fish in general? Yes, they can, especially if you’ve taken the time to create an environment in the aquarium that suits both the turtle and the fish. Can turtles live with Oscar fish in particular? Probably not.

The type of fish is one of those factors that will affect a turtle’s ability to coexist with it. While it is possible to keep Oscar fish and turtles in the same tank, this arrangement is typically discouraged because it doesn’t always end well. This is what you should know:

1. Size Differences

Because aquarium fish are known for eating any small enough creatures to fit in their mouths, the differences in size between the creatures that populate your tank matters. It will determine their ability to live peacefully with one another.

Oscar fish are large cichlids that can grow to a size of 12 inches. This makes them a threat to smaller fish. Turtles have an average size ranging from 5 to 12 inches. Depending on the type of turtle you have acquired, the size difference between Oscar fish and turtles isn’t large enough to make a significant difference.

Yet, your Oscar poses a significant danger to relatively small turtles. When a baby turtle meets an adult Oscar fish, it will probably not survive. Even if your Oscars haven’t matured yet, keep in mind that they are likely to hurt your turtles as they grow.

2. Aggressiveness and Temperament

The temperament is your biggest challenge where turtles and Oscar fish are concerned. First of all, you should know that turtles are omnivores. They like meat, and they will happily hunt and eat fish. They are a clear and present danger to any fish you add to the tank that isn’t significantly larger.

The chances of your turtles attacking your Oscars are quite high. The turtles will bite chunks out of your Oscar’s fins. On the other hand, Oscars are aggressive and highly territorial fish that might attack the turtles, injure them, and possibly even kill them.[1] 

That is especially true if you have a smaller species of turtle. Regardless of which creature attacks first, tanks with Oscars and turtles are often rife with the sort of aggression and violence that eventually leads to the death of one or both creatures.

3. Harsh Tank Requirements

If you already own fish and turtles are a new addition to your aquarium, you should know that they are not necessarily easy to rear. They have special requirements such as heat lamps, UVB light, and dry areas.[2]

You shouldn’t be so quick to add them to your Oscar fish tank unless you are ready to make the necessary adjustments. Typically, they live in water with temperatures ranging from 60 to 90 degrees F. Though, they are quite hardy and can even survive in temperatures as low as 50 degrees F.

None of those conditions necessarily clash with the requirements of Oscar fish which can survive in temperatures ranging from 74 to 81 degrees F and a pH ranging from 6 to 8. You can easily adjust the temperature and pH to suit your Oscar fish, and your turtles will be okay.

However, because both creatures are large, you need a much bigger tank than you would typically use when housing only Oscar fish. You should aim to at least 80 gallons.[3] Some turtles might surprise you with the size to which they can grow, especially if you added them to the tank when they were young.

But that isn’t your biggest challenge. Turtles are nowhere near as sensitive as Oscar Fish. In the wild, they have been known to live and thrive in dirty environments. The water in a tank with turtles will grow murky and smelly in the absence of a reliable and efficient filtration system.[4]

This is one of the reasons why Oscar fish and turtles are such a bad match. Not only are turtles capable of surviving in disgusting environments, but Oscars are some of the messiest fish you will encounter in an aquarium.

They have large appetites, and they produce quite a bit of waste.[5] As such, a tank with both Oscars and turtles requires a lot of attention. Keeping it clean is no easy task. As was mentioned above, the turtles will survive all the same. But if you fail to maintain the hygiene of your aquarium, your Oscars won’t be so lucky.

As you can see, it isn’t just a question of your Oscars and turtles’ temperament. Even if they are willing to coexist peacefully, a tank with both creatures requires more work than some aquarists are willing to do.

How to Make Oscar Fish and Turtles Coexist?

If you’re willing to work at it, you can take steps to maintain the peace between your Oscar fish and turtles, including:

1. Pick the Right Turtle

The nature of the relationship between your Oscar fish and turtles will depend on the type of turtle. Some species are friendlier than others. For instance, painted turtles only attack the smallest fish.

As such, they are less likely to clash with Oscars. Mud and musk turtles are also a proper choice since they have no interest in hunting. Older red-eared sliders are only interested in eating aquatic food. 

Snapping turtles, on the other hand, will not coexist with fish, least of all Oscars. If you can match your Oscars with a suitable turtle species, you have a decent chance of avoiding the conflict found in so many aquariums that feature turtles and Oscars.

2. Minimize Hunger

Try to keep your turtles well-fed. Turtles eat everything from leafy vegetables to mealworms, and crickets. Like most aquarium creatures, turtles are most dangerous when they are hungry. If you can keep their stomachs full, they are less likely to hunt the fish in your tank.

If your turtle has already matured, feed it every other day.[6] Younger ones (below the age of seven) should eat more frequently, although you should avoid these when it comes to Oscar fish. Keep in mind to remove the debris after 20 minutes of feeding to avoid pollution.

Oscars, on the other hand, should be fed two to three times a day.[7] You can choose between live food or formulated pellets. Either way, you should feed your Oscars regularly to avoid starvation. If you don’t, the gigantic fish is likely to turn to your turtles.

3. Introduce Plants and Decorations

Add plants and decorations to the tank. That includes flower pots, rocks, and driftwood. They will provide secure locations that fish can use to hide from turtles. However, this doesn’t always work. Turtles are big enough to force their way through obstacles of this sort. But it’s better than nothing.

As you can see in the video above, turtles typically swim at the bottom, mainly when rocks or hiding spots are nearby. Sometimes the turtle will stay behind robust decorations for a while, especially when it feels threatened.

4. Avoid Fish Food

If you don’t want your turtles to treat the other fish in the tank as food, don’t give them feeder fish. Otherwise, they will develop a taste for fish, which will compel them to feast on their tankmates, especially if they are smaller.

The same goes for your Oscar fish. To avoid hostility from their side, you shouldn’t habituate your Oscars into eating living fish. That will encourage them to chase after their food in your tank. Instead, try using formulated food, such as pellets.

5. Get the Right Tank

Keep your Oscars and turtles in a large tank. A smaller one usually encourages conflict because the fish and turtles keep running into one another. Get the most massive tank you can afford to ensure that Oscars and turtles can roam freely while also staying away from each other.

Some aquarists would encourage you to start with a tank of at least 125 gallons. You should also keep the population diluted, at least at the beginning. Try raising a single turtle with a single Oscar fish and see how the two get along.

Also, because of the mess that turtles and Oscars generate, you need a robust filtration system.[8] You should also change the water once or twice a week, depending on your observed conditions. Without a reliable filtration system, the tank’s environment will deteriorate, and your Oscars will pay the price.

What Fish Can You Keep with Turtles?

Fish like Guppies, Neon Tetras, Rosy Barbs, and Catfish can be kept with turtles since all species are relatively agile swimmers. Also, fish like Ropefish and Plecos are suitable tankmates for turtles since they are quite large and won’t fit in the turtle’s mouth.

  • Guppies – Guppies are beautiful fish. They are also fast and agile swimmers, and that makes them perfect tankmates because your turtles will have a difficult time catching them. That is often the key to pairing fish with turtles. You have to find fish that are fast enough to escape the jaws of the turtle.[9]
  • Neon Tetras – Neon Tetras are small, and that might trick you into concluding that they are a terrible match for turtles. However, neon tetras are incredibly fast swimmers. That makes them frustrating and challenging prey for turtles.[10]
  • Ropefish – Ropefish are timid creatures that spend a lot of time hiding. At 10-inches, they are large enough to live in a turtle tank.
  • Plecos – Plecos are also quite large. If you insert them in a tank with a turtle of similar size, they should be fine. Some plecos can grow to 18 inches, which is incredible.
  • Catfish – Some catfish are dangerous. They have sharp side-fins that can harm your turtles. Others, such as the Pictus catfish, make suitable companions. They are fast and agile, which is why your turtle will have a hard time eating them.
  • Rose Barb – The rose barb has an average size of 3 inches. However, it is a fast, agile, active, and alert creature. It will stay out of range of your turtle’s jaws.

Because turtles have a penchant for eating fish, you should always keep the cost of your fish in mind. Do not experiment with expensive fish by housing them with turtles. Start with varieties that are easier to replace, the kind you won’t miss if your turtle decides to eat them.

It is also worth reiterating the fact that turtles are not always the aggressors in an aquarium. Larger fish such as koi are more than capable of harming and killing turtles. Your choice of a tankmate is just as important to the turtle as it is to the fish.

Also Read: Oscar Fish And Goldfish: Can They Live Together?


Since both Oscars and turtles thrive in similar water conditions, they can potentially live side by side. That is more likely to happen when the tank is large enough (80 gallons), and there is a sufficient amount of decorations.

Also, in case there are considerable size differences between the two, hostility is likely to occur. That is why you should avoid baby turtles and immature Oscar fish. Instead, pick relatively big turtles, such as Mud and Musk.