The Oscar has been a popular aquarium fish for many years now. In fact, it is responsible for bringing many new aquarists into the hobby each year. The Oscar is playful, interesting, and many describe it as being the most “pet-like” fish you can keep in a glass box. One of the most distinguishing characteristics of the species includes a certain degree of "intelligence". More so than many other fish, Oscars appear to be keenly aware of their surroundings. When in captivity, they seem to recognize the person who feeds them!!!
As an aquarium fish, the Oscar has been subjected to breeding programs designed to bring out certain color combinations. Common Oscar variations available include the Tiger Oscar, Albino Oscar, Common Oscar, Fantail Oscar, and the Red Oscar. One that is the most similar to what is found in the wild is the Red Oscar. It is mostly greenish brown, with a large red streak on its underbelly. As a result of selective breeding, the captive born specimens that are available today are far different than the ones found in the wild.
Oscars become very large in captivity, so they need a large tank to live in. they need at least fifty gallons of room to be healthy. There are some fish that do well with Oscars. The biggest issue when pairing fish with Oscars is the size. They need to be housed with other large species if they are not going to make lunch out of their companions. Large Plecostomus, large cichlids, white tip sharks, tinfoil barbs, clown knife fish, clown loaches, and large eels all make appropriate tank mates for Oscars. Keep in mind, though, that you will need an extremely large tank to put six Oscars and some other species in he same tank.
The next important topic is care and feeding of Oscars in the captive environment. It is impossible to create a perfect replica of a natural habitat in your living room aquarium, but it is easy to come very close. As mentioned previously, Oscars are voracious eaters. This presents the first problem: feeding and cleaning up the mess. A basic diet for an Oscar should include high amounts of protein and vegetable matter. After ingesting any form of food, Oscars will generally release bits of it through their gills. This is normal. Oscar behavior in the aquarium is fascinating to watch. As mentioned previously, Oscars are considered to be the most "pet-like" of fish. Oscars enjoy digging up gravel and moving small rocks to pass the time. Other activities they enjoy are chasing a bobbing ping-pong ball and playing tug-o-war with a piece of colored hose.
Small Oscars can eat standard fish food flakes, but once they get larger than three inches, they need a more specific diet. They are often fed feeder goldfish, but cichlid pellet food is much better for them, since they are designed to bring out the bright coloring of the Oscars. Live food is another option, but it is more expensive, and pellets do just as well.
For some reason, Oscars tend to be very susceptible to hole in the head disease. This disease starts with small sores on the fish’s head above its eyes. As the sore grows, it eventually penetrates through the skin, creating a hole. It is believed that hole in the head is a result of poor water quality.