Can Oscar Fish Live Alone? Or, Get Depressed?

Oscar is a fascinating fish and almost everyone loves them. However, It takes a lot of patience and trial and error to make your tank set up just perfect for your oscar fish. When choosing the tankmates, you must be careful because oscar is not compatible with living with all types of fish. But, can oscar fish live alone?

Oscar fish can live alone; in fact, they do pretty well while kept alone. However, sometimes they may get depressed being lonely, and become inactive. Therefore, a careful selection of tank mates, decors, and other supplements should be put inside the tank so that oscar fish can live happily.

How to make them happy and active in the tank? Let’s explore some of the options you can think of to help your oscar live a healthy and playful life.

Basic Information About Oscar Fish & Care Requirements

Scientific Name Astronotus Ocellatus
Care Level Moderate
Temperament Terriotorial/Aggressive
Diet Omnivorous
Maximum Size 20 inches
Expected Lifespan 20 years
Ideal Tank Size (Minimum) 55-gallon
Compatibility Large passive fish
Water Temperature 77-82 degrees Fahrenheit
pH Level 6-8
Water Hardness 12-15 DH

Can Oscar Feel Depressed?

Oscar fish (Astronotus ocellatus) swimming underwater
Oscar fish (Astronotus ocellatus) swimming underwater

Living lonely in the tank may seem dull for oscar. They are intelligent fish, so they’ll love something that stimulates their brain.

The absence of entertainment can make oscar feel depressed. In addition, bullying tank mates, stress due to aggression, not enough space, absence of plants to fuss with, and sickness are the major causes of sadness in oscar.

How To Make Oscar Fish Happy?

Keeping oscar happy and healthy is not challenging, but a bit of care is required. Below are some ways you can keep your oscar active, and playful.

So, how to make oscar fish happy? In order to keep oscar fish happy and active first provide the ideal tank size and living environment for them. Keep, all the water parameters in the recommended range, and add tank mates that get along with oscar. In addition, feed a balanced diet and add some stuff to entertain the oscar fish.

Let’s dive into the details of how you can make your oscar fish happy.

Ensure Ideal Tanks Size & Proper Living Environment

Fish with fierce eyes
Oscar fish with fierce eyes living in poor water condition

Oscars love to have a spacious room to live in. They can grow 20 inches long in the right environment. They also grow very quickly, if you supply them right food & nutrition. On average they grow an inch per month. So, you can expect your oscar to grow 8-10 inches in the first year.

Once they are fully grown on average oscar fish reach 12-14 inches. However, as I said before, they can grow a maximum of 20 inches providing clean water & healthy food.

So, a bare minimum of 55-gallon is recommended for a single oscar fish. If coupled up with another one, at least a 75-gallon tank is necessary. In other words, for two oscar fish, a fishkeeper should consider having a 75-gallon tank.

For baby oscar fish of 2-3 inches in length, a 20-30 gallon tank is sufficient. However, as it grows, you will have to shift it to another tank that is larger.

In addition to the ample tank space, you need to set the temperature right for them. Maintaining the temperature is crucial for oscar because they are not hardy species, and are susceptible to disease. As they are tropical fish they prefer temperatures in the range of 77-82 degrees Fahrenheit.

To keep them disease free, happy, and healthy establish the right tank condition. In the below table you’ll get all the recommended ranges for water parameters.

Water ParametersIdeal Range For Oscar Fish
Ammonia0 mg/l
Nitrite0 mg/l
Nitrate<= 10 mg/l
Temperature77-82 degrees Fahrenheit
Hardness12~15 DH

Bring A Play Mate (Keeping Them In A Pair)

Bright oscar fish floating in aquarium. Astronotus ocellatus
Bright Oscar fish living in pairs in aquarium,

Pairing with another oscar is the most obvious choice. So, keep them in a pair so that they can interact with each other and play around.

But, can you keep two Oscars in the same tank? or will they kill each other?

Keeping two Oscars in the same tank is very possible. However, fighting with each other is also very common. That doesn’t lead to death usually. They chase each other, and that’s one way to remain busy. One way to prevent fighting is to bring them together at the same time in the tank.

Another aspect you should look at is the tank size. Bringing another oscar will demand a bigger tank. As a general rule, you should add 20 gallons for each additional oscar.

It applies equally if you want to keep multiple Oscars in the same tank. Try to keep oscar fish that are similar in size and provide plenty of room for them.

Not only oscar, but you can also include other fish species compatible living with oscar.

Multiple Oscar In A Planted Aquarium
Multiple Oscar In A Planted Aquarium

Feed Them Their Loved Diet

They are actually omnivores and love to eat both veggies and meat protein in both captivity and in the wild. People often make mistakes by feeding them all protein-based food. However, they can eat vegetables and fruits.

Provide a balanced diet; a mix of fruits, vegetables, and protein. I tried to get some ideas on what people feed their Oscars. They offer a wide variety of foods. They feed them pellets, fresh red meat, live fish, cucumber, peas, bloodworms, brine shrimp, live insects, and even blueberries.

Vegetables and fruits are not their primary diet. You should focus on protein-based food and feed other foods occasionally. You never overfed them, as it may cause severe ailments and make them sick.

Remove Fish That Makes Oscar Angry

Don’t put them in the same tank with other fish that oscar doesn’t like. That can make them angry, and put stress on them. So, you shouldn’t put any fish with oscar that constantly stresses them.

Instead, bring some beautiful bottom dweller fish, schooling fish, or fish that are not aggressive towards oscar and vice versa.

Bottom-feeder fish are a good option because they will keep the tank clean by eating excess foods, and algae. Oscar also can’t get them in its territory to catch and eat because oscar mostly occupies the middle & layer of the water.

The addition of schooling fish can also make your oscar busy and delightful. It will chase schooling fish to eat & may end up gobbling a few of them. The best practice is to keep a group of schooling fish, at least six of them so that oscar can’t target a specific one to chase and eat.

Some fish also cohabit peacefully with oscar. The list although not a long one, however, definitely, you’ll find some.

Entertain Your Lonely Oscar Fish

There are a lot of ways to entertain a single oscar in the tank. Oscars are curious about their surroundings. Bringing some playing objects can get their attention, and keep them entertained.

Oscars are intelligent pets; they can recognize their owners. So, playing with oscar is also a great way to entertain them.

I’ll write down some of the ideas to entertain your oscar.

  • Add Live food
  • Use A Mirror In The Tank
  • Toys
  • Moss Ball

Live food: In the wild Oscar fish keep themselves busy chasing live insects, worms, etc. One of my fellow fishkeepers feeds garden worms to his oscar fish, and it loves that.

You can also feed some live food such as cricket, mealworms, super worms, wax, shrimps, etc. and it’s cool watching your oscar eat them.

Although live food is very nutritious, it’s also a source of bacteria and viruses that can make your oscar sick. So, if you buy live food, make sure you purchase from a well-known shop.

Mirror: Some aquarists also add mirrors to their tank. Seeing their own reflection in the mirror oscar fish will think someone else is trying to invade their territory. So, they will flare up and fight.

Toys: Oscar fish like to play with toys. Various toys you can add to the tank for your oscar to play with. Some common toys are ping pong balls, fishing bobbers, waterwheels, floating logs, etc. Toys will make your keep oscar engaged, and won’t feel lonely.

Moss Ball: Oscar like move things around. Moss ball is a great toy for oscar. They love to play with it and move around. You can also consider adding some live plants. Plants provide a good hideaway for them and also add oxygen to the tank.

A fluval moss ball is another good choice; it’s an artificial one specially made for removing phosphate and nitrates from the water. Your oscar fish can play with these toys. In addition, you’ll get some added filtration for your tank.

Whatever decors or toys you include in your tank make sure there are no sharp edges on them. Otherwise, your oscar may get wounded moving around them and can get sick.

Oscar having a little bump in its chin
Oscar has a little bump on its chin

Signs Of Oscar Feeling Bored Living Alone?

There is some common syndrome that oscar demonstrates while feeling bored. Out of boredom, they can do a few activities that indicate something is not going right for them.

The most common sign of a bored oscar is not eating anything. Other signs are thrashing with tank accessories including decors, heating tubes, air pumps, filters, etc., and even they can hurt themselves deliberately.

Although, symptoms may vary from individual fish. However, providing them with some sort of entertainment won’t do any harm instead will keep them happy and healthy.

More Resources: Do oscar fish have teeth? (And Can They Bite Human)

Bottom Line

Oscar fish can live alone, and can potentially reach the maximum size. However, in order to make your oscar fish a happy life, you should consider a few aspects.

That includes the right tank setup, suitable tank mates, removing any bullying fish, proper diet, and providing some sort of entertainment to make them stimulated and energized.

If you own an oscar fish please share your experience in the comment section below. It’ll help my readers to get some insights from other perspectives. Happy oscar keeping.

Sujit Modak

Leave a Comment