A Guide on Taking Care of Oscars, the Most Popular Fish Among Pet Owners

Brown, Silver, and Black Oscar Fish

Getting To Know Oscars

While the popular American pets remain to be man’s best friend and the purring feline house cat, people are beginning to become more familiar with another pet that lives within the confines of a glassed Aquarium. Oscars, are the most popular fish among pet owners in America because of there large size and very sharp personality. Many of you may be interested in the Oscar and would like to have one inside your brand spanking new fish tank. However, there are a few things you should know about the gullible looking fish before you invest money and time in them. Unlike goldfish, these tank mates require lots of time, money and energy to ensure that they live a long time. There are important things that you should know before buying an Oscar.

Purchasing an Oscar

Most pet stores carry Oscars at a very small size. Petsmart and Petco are good stores to go to when looking for an Oscar because their prices are pretty cheap. The average price range of an Oscar is $4.99 to $6.99. Small Oscars are very active and full of personality. With any fish that you purchase, look for the one with the most energy. As they grow older, Oscars will settle down and become more docile.

Tank Size

The size of a small Oscar can be very deceiving. Their size can range from 1-3 inches long. However, they have a rapid growth rate of about an inch per month until they reach their adult size of about 12-14 inches. It is very important that you have an aquarium big enough to hold an Oscar. A 30 gallon fish tank for one Oscar is sufficient. Holding more than one of these cichlids in a 30 gallon tank may result in very murky water due to constant bowel movements from eating and fighting. Oscars are aggressive and territorial fish. They need enough space of their own in a tank to coexist with other fish of their size. I recommend that the minimum size for at least two Oscars is a 55 gallon fish tank.


It is important that you have a decent filter for your tank when housing Oscars. They can be very filthy at times and will need to have a sufficient filter. Personally, I have two filters working together to help the water stay clear and clean. Dirty and bacteria-filled water will result in your Oscar having a disease called HITH (Hole in the Head). This decease is external, with huge crater like holes on the head of your fish. Oscars need a water temperature between 72°F – 78°F. Therefore, you will need an aquarium heater as well as a tank thermometer to monitor the temperature. Due to their hardiness, Oscars need the pH water level (the hardiness of the water) at about 6-8 to maintain there survival. 

That is pretty high for most aquarium fish. You can purchase a chemical called “Proper PH” at your local pet store. Make sure that you get the desired level and maintain it at all times. Oscars do not like lots of light, so it is important to have one side of the aquarium with light and another side dark. In the wild, Oscars like to hide behind and under large rocks and logs. To similate the wild as mush as possible, you can purchase large rocks (depending on the size of your tank) for your aquarium landscape. Do not bother with artifical plants for your Oscars. They are known to continuously dig them up and knock them over.  

Feeding Your Oscars

I have come to realize that Oscars are very greedy and will eat anything that can fit in their mouth. It is important that you give them a variety of food to help them maintain a variety in their diet. Oscars eat live fish and it is quite safe to feed them small goldfish feeders every once in a while. However, be very cautious of always feeding them goldfish from the pet store. Feeders from a pet store are usually crammed in one tank. As a result, some of them may carry parasites that can be harmful to your pet(s). Live crickets are also available at the pet store and are much safer than goldfish feeders. Also, try feeding your Oscars cichlid pellets and flakes (also available at the Pet Store) to mix up their diet. 

Other Tank Mates for your Oscars

Generally, Oscars are very and calm fish. However, they are very territorial and are known to be aggresive at times. It is not wise to put any fish in the aquarium that is smaller than your Oscar. This will result in the Oscars either killing or eating the smaller fish. Larger and much more agressive cichlids may be of harm to your Oscars. I reccomend that you only put fish in the tank that is of the same size as your Oscars.  

Cleaning Your Fish Tank

Like all other aquariums and fish, it is important that you clean your tank at least once every two weeks, especially when you have Oscars. Make sure that you have an aquarium water vacuum, able to suck out the gunk and wasted bowel at the bottom of the tank and in between the gravel. When changing the water, do not take out more than half. Doing so may result in changing the environment of your fish. It is much safe to change 20% of the water with each cleaning. Make sure you clean the filters as well and change the cartridges inside.

Watching Your Oscars Grow

Oscars are very intelligent fish. You will be amazed with the personality that they possess. As mentioned before, Oscars are very greedy and have been known to recognize the person that feeds them. I get home from work everyday at 5pm and once I come into the room, both of my Oscars dash into the corner where I usually put the food in. I’ve had my two Oscars for 6 years now, and they are both about 13 inches long. If you take care of your Oscars properly, they can last for a very long time.