Amazing oscar aquarium fish life cycle

Oscar fish can be found anywhere in the Amazon River Basin. It is a South American species belonging to the cichlid family and native to countries like Peru, Columbia, Brazil and Ecuador. They are also known as Velvet cichlid, Walnut Cichlid or Peacock Cichlid. Their scientific name is Astronotus ocellatus. Oscars are fresh water fish and typically live in low-flow, slow-moving white water. If there is the greenery, plants and branches in the water then it serve as the best hiding place from predators.

They are well known among hobbyist for their intelligence as they have the ability to recognize their owner and may learn tricks. They are popular as pet for their inquisitive or curious nature, which is full of personality and attracts viewers. Oscars are attracted by their appearance, colors, intelligence and social behaviors. Their aggression makes them infamous for keeping as pet but they swim so gracefully that they prove that looks can be deceiving. They are fairly large fish and often grow few inches in a month or two.

Why to Keep Oscar Fish as the Pet?

Oscars are popular fresh water fish. They are famous among aquarist for their playful behavior, intelligence levels and beautiful colorings. They have impeccable memory and among one of the few aquarium pets that can be trained to do tricks and able to distinguish their owner. They are appealing due to the way they interact with the humans. Because of their behavior they are nicknamed as “River or Water dog” as they have ability of shaking or wagging their head and tail much like dogs. Although they don’t have an attractive look but they have a way of winning people heart with their unusual behaviors. They have a mind of their own which means that they show a sense of purpose in their movements and don’t swim aimlessly in the tank. Oscars are very affectionate and because of their intelligence they are adapted as a pet, the owner may train them to feed from their hand even. They have an aesthetic sense as they may restyle the interior of the tank in the way they want, by moving the objects according to their choice. Thus your Oscar has a tendency to re-arrange and re-decorate a tank. They are moody in nature and make their mood swings noticeable. Oscars don’t like change in their environment and seen sulking for various reasons. Thus they can be the one of the best addition to your fish tank at your home, office and work places.

How Does Oscar Fish Look Like?

The wild Oscar fish are dark in color and have orange ringed spots known as Ocelli. The Oscar Fish can alter their coloration which is a trait that facilitates combat and territorial behavior. The young Oscar fish are different from adult ones in coloration. The young Oscar fish are striped with white and orange bands with spotted heads. They are also named as peacock cichlids because they have peacock like tail. The Oscar Fish gain the weight up-to 1.6 kg and length of 15 inches long in the wild where in captivity on average the Oscar fish grows up-to 9-12 inches long.

What are the Types of Oscar Fish?

There are three major types of Oscar fish

  • Tiger Oscar Fish
  • Red Oscar Fish
  • Albino Oscar Fish

Tiger Oscar Fish:

They are the original Oscar fish. They are known to be the wild Oscars and are pure breed thus, no anomaly can be found in them. Oscars are found to have orange markings on the chocolate brown or gray scales. They are known for having actual conduct and qualities of the Oscars.

Red Oscar Fish:

They are found in different shades of red which includes bright red, deep red, rusty orang etc. They don’t have the red markings or the patchy spots on the bodies. Their scale gives them the velvety look which makes them look more beautiful and attractive.

Albino Oscar Fish:

They are white in color and can found in the combination of orange and red. Albino Oscar fish are usually seen with the white base. Their shiny scales give them the velvety look. The real Albino Oscar fish are recognized by their white base coat and red eyes.

The cross breed types of Oscar fish are also available which includes;

  • Lutino Oscar Fish
  • Lemon Oscar Fish
  • Yellow Oscar Fish
  • Veil Tail Oscar Fish
  • Breeding Oscar Fish
  • Albino Tiger Fish
  • Red Lutino Fish
  • Wild Oscar Fish

What are the Size and Life Span of Oscar Fish?

Oscar Fish can get quite large, such as reaching the length of 12-14 inches long where in the wild they may grow slightly larger and according to the reports these fish grows up to 18 inches. The Oscar baby fish are as small as 1-2 inches in size and under the right condition they may grow at a rate of 1 inch per month, thus Oscars grow quite fast.

The life span of Oscars depends on the condition of the tank, under the right and favorable conditions with the proper care and diet; they may grow up to 15 years. The average life span of Oscar Fish is 10-12 years. If you want your Oscar fish to live for a longer time with you, it is recommended to give them the proper care and right conditions so that they may thrive well. They are a wonderful creature and serve as your great companions.

How to Differentiate Male Oscar Fish from Female?

It is not an easy job to differentiate a female Oscar fish from a male fish. It takes about 2 years for Oscars to fully mature. At the age of 12 to 15 months Oscars are 4-5 inches long and one can examine their reproductive parts. Close observation is required to correctly determine the gender of the fish, both the male and female have the same two openings and one is anus and other is the reproductive organ. Male Oscar fish has a small spike like sexual organ where the female reproductive organ is blunter and wider, it is the tube where the eggs are released. The two holes are of the same size in the male Oscar fish where in the female Oscar fish the one hole is bigger, which is the egg tube. The other differentiating factor is that the female’s skin is lighter than the male’s skin. The process of observing gender of Oscar fish is named as venting.

Which are the Tank mates of Oscar Fish?

Although the Oscars are one of the most entertaining specie of the fresh water fish-keeping but in captivity they show more aggressive behavior making it difficult for the owner to keep other fish along with them. Only the fish that are large, strong and hardy enough to hold their own against an Oscar can be kept along with them. The few compatible Oscar tank mate are as follows:

  • Black Convict Cichlids
  • Silver Dollars
  • Firemouth Cichlid
  • Severum Cichlid
  • Green Terror Cichlid
  • Jack Dempsey Cichlids
  • Bichir
  • Plecostomus

All the types of species can’t stay together because of the differences in their nature and behavior as some have predator-prey relationship and some are aggressive to each other. As we know that Oscars are aggressive in nature because of which they can’t be kept with all types of species. There is a list of species which should be avoided to be kept with the Oscars:

  • Don’t make small and slow moving fish, tank-mates of Oscars as they will eat them up.
  • Small Cat fish in the Oscar fish tank can be the threat to their lives as they have spines on their fins.
  • Try to avoid placing peace loving large fish in the Oscar fish tank like Discus.
  • Avoid the species that are sensitive and conscious about the water conditions as Oscars are messy eaters and have high nitrates in the water.

Aquarium for the Oscar Fish:

Aquarium or fish tank is the right home for your aquatic pet, where they can live happily, have a healthy life and thrive well. If you want to have any aquatic pet like fish for you then you must bring a right sized tank for your pet according to the specie you are going to bring home. Setting up the beautiful tank for your pet is an amazing job and loved by most of the people who love to have aquatic pets. Aquarium is one of the beautiful things that enhance the beauty of your living places. Well maintenance of your fish tank can ensure the good health and long life of your pet fish. Oscars are intelligent fish and kept by most of the people as a pet because of their tendency to learn tricks and respond to their owners. Oscars are larger in size and requires more space to thrive well in the tank. It is relatively easy to take care of them as long as you give them the right food and keep their tank clean. Under the proper care and suitable tank condition they can accompany you for a long time.

Setting up and Maintaining Ideal Oscar Fish Tank:

It is required to give your fish the best environment, which fulfills all their requirements. Oscars are large fish and they are extremely sensitive to the water conditions. You should make sure that your fish tank is suited to their preferences. In order to setup an ideal aquarium for your fish the very first thing is to bring a right sized tank.

  • Right-Sized Tank for the Oscar Fish

The Oscars are the large fish and may grow up to 25-28 cm or 10-11 inches in size so a relatively larger tank is required to place an Oscar fish in the tank. According to the study a tank with the capacity of 55 gallons is at-least required to keep a single Oscar fish and in order to keep the tank mates with Oscar fish you definitely requires the tank with much more Capacity. For example, if you want to keep 2 Oscar fish then you should have a tank with 120 gallons capacity. If you want to keep other species with your single Oscar fish as tank-mates then a tank of 75 Gallons or larger will be required. If you place your pet in the place smaller than required, this will result in the increased stress and make them unhealthy which may cause serious harm to your Oscar fish.

  • Substrate for the Oscar Fish Tank:

Both sand and gravel work well as substrate for the Oscar fish tank. It is good to select the substrate that filters well as Oscar produces a lot of waste. If you select the sand as a substrate you must use coarse sand which is less likely to get sucked into the filter. Oscars enjoy digging and taking in substrate and spitting it out is their another hobby which may damage the filter so you must use pre-filter into the tank. It is recommended not to use anything sharp which may damage the fish during their play. Don’t add too much of substrate into the tank i.e. 1-1.5 inches of substrate is more than enough as more amount of the substrate will have more uneaten food which makes tank unhealthy.

  • Filter in the Oscar Fish Tank:

Oscars are very sensitive to water conditions and along with this they are slovenly and produce more waste than most of the fish species. With this they also love to rearrange their tank and constantly stirring up the bottom for this purpose. Keeping in mind this all you require a high-capacity water filter in the tank which can filter your entire volume of water at-least four times in an hour. Canister and Hang on back filter placed as backup can help in handling so much of mess and filter the water properly. The filter chosen for the Oscar Fish tank should be rated higher than the capacity of your tank. For example, for 75 gallons tank you’d want at least a 100 gallons filter.

  • Heater and thermometer for the Oscar Fish Tank:

Oscars in natural condition lives in the warm water of the Amazon River Basin. They are sensitive to water temperature changes. They stay happy at the 77 degrees Fahrenheit where they can tolerate the temperature range of 74-81 degrees Fahrenheit. An external thermometer should be used to check the temperature as if it is inside Oscar may break it. Heater should be adjusted accordingly to keep the water temperature steady and suitable for Oscars. Choose the heater which is accurate for the size of your fish tank.

  • pH Level in the Tank:

To keep the fish healthy and happy in the tank it is required to maintain their desired pH level in the tank which they have in wild. Oscars live in the water with pH level of 7.2 so you have to maintain the pH level in the tank ranging between 6 and 8. Water testing is required to adjust the pH level in the tank accordingly. If the pH is too low you may add 1 tsp of baking soda for every 5 gallons of water. If the pH is too high you can add clumps of peat moss in the aquarium to lower the pH in the tank. Quick and drastic changes are not recommended to adjust the pH level as it may hurt the fish.

  • Plants and Decorative in the Oscar fish Tank:

Beside the fact that Oscar is not a shy fish, it is still important to give them places to hide so that they may feel more comfortable. They may hide among objects in order to feel safe. Oscars like to move small objects around them and rearrange their territory. It is advisable to place heavy objects if you don’t want your pet to move them. Breakable decorative should not place in the tank. If you place live plants inside the tank your fish will tear them up a bit. Fake plants, driftwood and sturdy decoration like PVC pipes and stone caves are the best option for your Oscar fish tank. The decorative placed in the tank should not have sharp edges or rough texture.

It is important to cover your Oscar fish tank cover with the tight lid, as Oscars like to jump and may jump out of the tank. Medium-sized Oscar can even lift the lid right off the tank if it is not tight enough. You should aim to have a water turnover of 4 times per hour in the Oscar fish tank as Oscars love moderate-high flow water.

What Does Oscar Fish Eat in Wild?

In the wild Oscar fish eat insects, worms, smaller fish, plants berries and any fruit they find in their habitat.

What Does Oscar Fish Eat in Captivity?

In the captivity, try to replicate the natural diet of the Oscar fish as closely as possible. Their diet should be high-protein, high-quality with a variety of frozen, freeze-dried and processed foods. 80% of your Oscar fish diet should be commercial cichlid pellet which contains krill, whole fish or shrimps. They need a food that mostly made of meat. Pellet containing algae or green plant materials must be used to ensure that your fish is getting all the required vitamins. The supplementary food you can give to your Oscar fish may include Crickets, Grasshoppers, Mealworms, Locusts, Dead prawns and Shrimps. Oscar food should be mainly made up of lean food so one should avoid poultry and beef heart.

What is the Amount and Duration of Feeding Oscar Fish?

Baby Oscars are voracious eaters and they are found hungry all the time but one should limit the amount of food given to them as overfeeding can make them sick. Smaller Oscars should be given 3-4 pellets once and add more when Oscar has eaten it. Feed your Oscar in this way for 3 minutes and then stop it. Only feed your Oscar once it has eaten all the food.

This process of feeding your fish should be repeated 2-3 times a day and remove uneaten food from the tank quickly in order to avoid upsetting water quality.

When the baby Oscar reaches 5 inches length, then you should feed them twice a day and supplement larger living animals.

What are the Common Diseases of Oscar Fish?

Oscar fish are rarely got sick but there are many diseases that affect Oscar fish. Here are enlisted few diseases which affects the Oscar fish.

  • Hole in the Head(HITH) :


  • Flagellated protozoans and bacteria
  • Nutritional deficiencies are the cause of this disease.

The actual reason of this disease is not known yet.


  • Small white spots around the fish’s eye region and on the head
  • Large holes and sores on the body
  • Loss of appetite


  • Flagyl or metronidazole
  • Improving tank conditions
  • Ich / White Spot Disease:


  • Protozoan parasite (Ichthyophthirius multifiliis)


  • Loss of appetite
  • White spots on the gills and skills
  • Rubbing body against walls and objects in the tank
  • Increase in gills movement
  • Fish lies on the bottom of the tank
  • Reddening of the fins


  • Formalin (Formaldehyde)
  • Arciflavin
  • Victoria Green
  • Salt
  • Malachite Green
  • Copper Sulfate
  • Fin / Tail Rot Disease:


  • Bacterial infection is the cause of this disease
  • Poor environmental conditions


  • Blackened, tattered or bloody fins
  • Lethargy
  • Loss of appetite
  • Slimy or milky appearance of the fins or body
  • Portion of fins may fall off


  • Chloramphenicol
  • Tetracycline
  • Oxytetracycline
  • 20-30% water change prior treatment
  • Aquarium Salt
  • Pop-eye Disease:


  • Chronically poor water condition


  • Swollen or bulging eye
  • Cloudy appearance to the eye


  • Add aquarium Salt
  • Use antibiotic products
  • Improve the water quality
  • Dropsy or Bloating:


  • Overfeeding
  • Constipation


  • Uncontrolled or erratic swimming
  • Bloated appearance
  • Hard feces trailing from the fish
  • Swollen abdomen
  • Loss of appetite
  • Raised appearance to the scales