Oscar Fish Care Guide, the Intelligent Aquarium Pet

Oscar Fish Care Guide

The Oscar fish is a predatory fish native to the Amazon basin, and this fish species is from the cichlid family. You can find them also in India, China, and Australia. Oscar fish is very popular in the aquarium trade.

They are one of the most intelligent fish species. It can easily be trained to play tricks in the aquarium tank. In this article, I’ll talk about their characteristics and requirements to provide a complete Oscar fish care guide. 

They are playful, smart, and courageous. Oscar fish interact with humans, and that’s an incredible experience for aquarium keepers. You can hand feed them. Their mannerism is entertaining to watch.

Oscar fish are famous for their intelligence and infamous for aggression. They are sluggish in movement but capable of ambushing prey over short distances. Hence they are dangerous for smaller fish. Oscar fish can be a little tough choice for beginners, but they are amusing characters.


Oscar Fish, some Basic Things to Know

Scientific Name: Astronotus ocellatus

Care Level: Moderate

Temperament: Territorial/Aggressive

Diet: Carnivorous

Maximum Size: 18″

Expected Lifespan: Up to 20 Years

Ideal Tank Size (Minimum): 50 Gallons

Compatibility: Large passive fish

Water temperature: 75-80°F

pH levels: Between 6 and 8

Water hardness: 12-15 DH


Oscar fish have a wide variety of coloration. They are classified into different types based on their appearance. They can be red, orange, black, blue, white, green, and lemon with many different combinations and color patterns. They have a long, egg-shaped body with symmetrical caudal fins. Oscar fish have large aggressive-looking eyes.


Oscar fish tends to be territorial and aggressive, but that’s a one-sided story! They are quite intelligent and social creatures. They are one of the few fish that you can train to do tricks. They love to play and communicate with humans.

Yet they can be ferocious when the deal is about food and mating! Due to their intolerant behavior, an inexperienced aquarist may face difficulties to handle Oscar fish. And they are not an ideal community fish to keep with others.

Unlike most other predatory carnivores, Oscar fish are very protective parents for their children. They defend their territories and protect their babies very carefully. Brood-caring is a rare phenomenon among fish species, which signifies their intelligence.

Size and Life Span

The average size of Oscar fish in captivity is 12 inches, but they can grow up to 18 inches in the wild. In a sufficiently spacious aquarium, Oscar fish can grow as big as 16 inches. But they need a proper diet and stress-free life to attain that size.

Oscar fish has a relatively long lifespan, which is 15 years on average. But if you can provide them an ideal condition and good care, few more years can be expected. Oscar fish surviving 20 years in an aquarium is not impossible. Having so long time with an intelligent species can create emotional bonding between the pet and the owner.

Some Popular Types of Oscar Fish

Tiger Oscar Fish

Tiger Oscar Fish

Ther are aggressive and colorful! Aggression is part of their personality, which suits them nicely. They have black and orange coloration that is very attractive. Tiger Oscar fish is the most popular aquarium fish among Oscars. The appearance with black and orange stripes resembles that of a tiger. A fully grown Tiger Oscar fish can grow up to 15 inches.

Albino Oscar Fish

Albino Oscar Fish

Albino Oscars are very pretty looking. They are almost entirely white with orange and red lattice. The density and design of the orange pattern are not the same for all individuals. Variation in color makes them highly sought for aquarium keeping.

Red Oscar Fish

Some of them can be entirely red, while others may have a two-colored appearance dominated by red. Their fins can be black, and eyes will have orange rims. The Red Oscar can grow as large as 16 inches. Large aquariums above 60 gallons are suitable for them. A deep sand substrate with a few larger rocks can make them happy. They add more colors to your aquarium, no doubt!

Veil Tail Oscar Fish

The name suggests their specialty! They have long veil-like tails, which makes them unique, attractive, and delicate. Veil Tail Oscars have variations in colors. They can be white, a combination of black-orange, or reddish in appearance. Whatever the color is, they look beautiful with their trademark tails, and whenever they expand them, it becomes entertaining to watch.

Lemon Oscar Fish

lemon oscar fish

Most of them have a bright lemon color that makes them distinguishable from all other species of Oscar. Some of them may not have an entirely lemon color appearance; instead, a lemon-green gradient on a white body. Proper nutrition and healthy water condition are favorable for flourishing their attractive body color.

Oscar Fish Care

Food and Diet

Oscar fish are carnivorous, and they love to feed on living foods, but the young ones tend to feed on flakes. They have a voracious appetite, and they want to eat everything fits inside their mouth. So they are not picky about the food, and its good news for the Oscar owners. Though Oscars are primarily meat-eaters, it’s not unusual for them to eat plants and vegetables.

In aquariums, you can feed them Cichlid-friendly prepared pellets and flakes. Bloodworms and brine shrimps are common foods that Oscar owners provide them. You can even feed them live insects like crickets and grasshoppers. For additional supplementation, you can try with fruits and nuts, providing them chopping off into pieces.

Tank and Water Conditions

Oscar fish need large tanks to have an ideal habitat. A 55-gallon tank is a minimum requirement for a single Oscar. You can keep more than one in an aquarium. In that case, the thumb rule is adding 25 gallons for every additional member. That means 80 gallons for two and 105 gallons for three Oscars.

They are not comfortable in a congested place, and when they are uncomfortable, they become angry. Oscars are not compatible with most other fish species. They will prey on small fish and fight with large active fish. Only large peaceful, passive fish can be their tankmates.

Deep sand substrate combined with few large rocks can accent natural flavors for the Oscar fish. They may have a tendency to dig up plants, so if you put them in a planted aquarium, make sure plants are deeply rooted.

Sometimes Oscars may try to jump out of the tank for searching foods (or adventures! Whatever! They know better.) Your job is to cover the tank with a lid.

Oscar fish are not too sensitive to water conditions and can adapt to variations. Like all other tropical fish, they prefer warmer water of 75-80°F. They are okay with the pH ranging from 6 to 8, and the hardness of 12- 15 DH.

Disease and Cure

Oscars are hardy fish and don’t easily get infected with any disease. But there is one particular disease that you should be careful about. ‘The hole in the head’ is that disease, and it can be dangerous for your Oscar if not treated with early symptoms.

At the primary stage of this infection, one or two holes appear on the fish’s head and can get worse day by day. If you observe any symptom, you should immediately start medication and change the aquarium water.

Metronidazole is a common medication for hole-in-the-head, but it is better to seek an expert vet’s prescription.

The disease is preventable by maintaining healthy water conditions. For the better health of Oscar fish, you should provide vitamin and nutrient-rich food. Clean aquarium environment and proper diet is the key to prevent all sorts of infections.

Final Words

Having Oscar fish as aquatic pets will be entertaining. There are some challenging parts of having Oscars in your aquarium, but it’s manageable. You just need to know the basic tips and plan accordingly.

It is not wise to put a newly bought Oscar in an existing tank, so you need to plan the entire tank for the Oscars. I will not suggest keeping Oscars with other community tank fish, rather make a dedicated Oscar tank and keep more than one of them.

This intelligent little creature will bring your fishkeeping experience to a new level. So, let me know your thoughts. If you are already an Oscar owner, I’ll be glad if you share your experience in the comment box.

1 thought on “Oscar Fish Care Guide, the Intelligent Aquarium Pet”

  1. Hi Sujit,
    I was searching for the options for pet. I have read your blog and love the way you have explain about the fish as a pet .(The Oscar Fish). You have covered all the minute details like water conditions, behavior of fish, disease and cure. Looking for new blogs from your side.
    You can also read about more best pets at https://hypoallergenicpetbreeds.com/category/best-pets/

    Michael Smith

Leave a Comment

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

Sujit Modak Aquarium Tales Owner
Sujit Modak

Hello, everyone! Welcome to my aquarium blog. Fishkeeping is my passion, and I started this fascinating hobby back in 2006. Besides my engineering profession, I deeply studied many fishkeeping topics since I started building my home aquarium. I researched effective aquarium filtration and lighting of planted aquariums. I am keeping 20+ species of freshwater and saltwater fish as my aquatic pet collection. I successfully experimented with a complex ecosystem inside the aquarium, biotope aquariums, aquaponics, etc. I would love to share some learnings from my hands-on experience of the last 14 years. Hopefully, my sharing will be somewhat helpful to make your aquarium journey awesome! 

Copyright © 2020. All rights reserved by Aquarium Tales