Tips and Facts about the Oscar Fish

Oscar fish cichlids are some of the most beautiful and intelligent tropical aquarium fish. Their native habitat is the South American Amazon Basin, but they can also be found in French Guyana or Suriname. Oscars are also known as velvet cichlid or marble cichlid (Acara compressus, Acara hyposticta, or Astronotus ocellatus zebra) because of their color variations.

Oscar Fish 2

In the wild, the velvet cichlid can grow over 14 inches long, but most captive Oscars can only reach about 11-12 inches, live up to 11-13 years, and reach a weight of 3.5 pounds.

Wild velvet cichlids are usually dark colored, with yellow spots (ocelli, these giving them the scientific name of Astronotus ocellatus). Young Oscars have different coloration than the adults; they have white and orange stripes and spotted heads.

Due to interbreeding wild specimens throughout time, there are now many types of Oscar cichlids besides the original, wild ones:

  • Tiger Oscar fish with marbled spots of red pigmentation;
  • Albino tiger Oscar fish;
  • Red Oscar fish and red lutino Oscar are mainly red colored on the sides;
  • Albino Oscar;
  • Veil tail Oscars have longer fins than other varieties;


Oscar fish may eat a wide variety of foods; actually, they taste mainly everything in the aquarium. Their best diet would consist of a balance between live foods and processed ones. Before choosing any food for your velvet cichlids, it is extremely important to ensure the bits are smaller than the fish’s mouth.

In the wild, Oscars would eat a variety of insects and crustaceans. Live foods are good for stimulating growth, but a large quantity can cause parasites, obesity, or fatty liver disease. You can occasionally feed them mussels, prawns, shrimp, or meal worms. Small feeder fish may also be part of their diet, provided they are very healthy. It is best for the owners to raise their own feeder fish, as fish from pet stores or raised in fish farms can bear diseases transmittable to the Oscar fish. The most affordable and disease-free feeder fish are the guppy or the rosy red minnows.

Processed foods are the easiest to find in pet stores. Suitable commercial food for the marble cichlid includes brine shrimp, blood worms, jumbo krill, and beef heart. General cichlid pellets, flakes, wafers, crisps, or tablets are also suitable for Oscars, but they must always be smaller than the fish’s mouth. Always keep an eye on the aquarium while feeding flakes or crisps, as the velvet cichlids tend to chew and leave small particles of food behind, which can lead to unclean water in short time.

Alternatively, you can also feed your Oscars fruits or nuts usually occurring in the tropical and subtropical areas of South America, but be aware these foods are only consumed in the wild on a seasonal basis. Some aquarists have experimented with various local vegetables from the supermarket and it seems frozen peas work very well for the marble cichlids. It has been noticed that peas help enhance the vigor and colors of the Oscars and most of them really love peas. However, always keep in mind Oscar fish are predatory animals, so meaty foods should always be the base of their diet.

Finally, keep in mind a healthy and happy fish needs variety in its diet, so always try to offer your Oscar fish different foods and supplements on a daily basis.

Oscar Fish

Oscar Fish Fun Facts

  • The Oscars are also called “river dog” or “water dog” because of the way they interact with their owners. They shake their tail and head just like dogs do, which is the reason people fall quickly in love with them.
  • Although there’s a slight resemblance, Oscar fish are actually not closely related to Piranhas.
  • They like to “redecorate” their aquarium by moving things around and excavating the substrate, so it’s easier to leave it like it is. They also seem to “play” with objects placed around their tank and can even be trained to knock balls into small nets or swim through loops.
  • The Oscar fish can actually get to know their owners and even eat from their hand.
  • Some people like to taxidermy their Oscars, but they are very few. This is why it is very pricey to have them taken to a taxidermist. This is also a very uncommon practice for taxidermists, as the fish need to be carved before stretching the skin over them.

Oscar fish are fascinating animals. First, because of their beautiful and vibrant colors of wild specimens, as well as interbred ones, and second because of their joyful and curious behavior, as well as being quite smart. These qualities make the velvet cichlids very popular among aquarium owners.

13 thoughts on “Tips and Facts about the Oscar Fish”

  1. I have a full grown Tiger Oscar who weighs about 3.5 lbs. Recently after feeding him some large earthworks he’s started acting strange & swimming back & forth really fast & jumping up trying to knock the top off of his aquarium. He hit it so hard he knocked the light out! I’ve looked at him & haven’t noticed any holes on his head & no ick is present. What could be causing this? I’m afraid he’s going to hurt himself if I don’t find out what is wrong with him. He’s in a 35 gallon aquarium, by himself, with his toys.

    • Do you usually feed hm live food? I wonder if the live food brought out the aggression side, and thats whats causing the behavior? Also,did he start this after the worms were gone? Maybe he wants more? I know our Oscar seems to prefer different things sometimes, and have noticed if we give her live food it causes a little bit of aggression. I will say she hits the top of our tank during times that I see no reason for.And seems to stop doing it all of a sudden. The really are funny creatures that have a bunch of personality!!

    • It might be worth the read, I know that he started acting this way after he ate but it sounds like his tank might be too small.

      I found this on,

      “Most aquarists agree that a 55 US gallon tank is the absolute minimum tank size to house an adult oscar. This is because a smaller tank simply does not have enough water in it to dillute the waste produced by the oscar. It is also because a smaller tank simply does not have enough room for the oscar to swim. A standard 55 gal tank is about 4 feet (122 cm) long and one foot (30 cm) wide. Since an average Oscar grows to about 12 inches (30 cm), a 55 gal barely provides room to turn, and provides a straight line swimming distance of about 4 body lengths, which is not much.”

    • A 35 gallon tank is WAYYYY too small for an oscar. I would strongly suggest you either upgrade to at least a 75 gallon or rehome him.

  2. I have two Oscars the youngest one two days. He was three years old. Now since Oscar died my other Oscar is depressed. He is about fifteen years old. What can I do for him. I started talking to him. For two days he just sat in one spot looking at himself mirror. But since I started talking him he is moving around to other side fish tank.


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