Oscar © Nishad

Common Name: Oscar
Latin Name: Astronotus Ocellatus
Origin: South America
Temperature: 72-80°F
Ease Of Keeping: Moderate
Aggressivness: Moderate
Lighting: Subdued
Adult Size: 14″ (35cm)
Minimum Tank Size: 55
Feeding: Omnivorous
Spawning Method: Egg layer

Oscars are friendly, and can be very interactive with their owner. They can be taught to jump out of the water to get their food, and will play with toys that float. Our Oscars played with plastic (cat toy) balls.

They cover all areas of the tank, but can mainly be seen in the middle or closer to the bottom resting. They are quick to get to the top as you get closer to the tank. It’s either food time or play time…..both of which they love.

As interactive as they are, it’s very important not to leave them lonely. Another Oscar or cichlid who can be housed with an Oscar is ideal. A bored Oscar can often lead to different characteristics as far as his behavior goes.

Oscars are omnivorous. They will eat just about anything they can fit into their mouth. Cichlid pellets (high in Vitamin C, protein, and vegetable matter), prawn, bloodworms, & earthworms are just some of what they can be fed. Feeder fish can be fed to Oscars, but it is not suggested unless you breed your own and are positively sure they are free of diseases. All too often, Oscars get sick due to the malnourished and often sickly feeders that are purchased from local fish stores.

Oscars have 2 sets of teeth. 1 set in their mouth, and one set in their throat. When feeding Oscars, you’ll notice food coming out of their gill plates. This is from the manipulating of the food that is going on with the teeth in their throat. The teeth in their jaws are pretty much to grasp on to it’s food/prey.

Seeing how an Oscar eats, and knowing how much they can eat (big waste producers) leads us to filtration. You can never have too much filtration. Adequate filtration is a must, as their water will quickly become polluted. Stay away from UGF’s, as they are “ground moving” fish. They will have no problem cracking the plates, or evening bruising themselves by ramming into the plates.

Heaters, well that’s another thing to think about. They are notorious for breaking heaters. A simple hang on the back glass heater stands no chance when it comes to Oscars. You’ll not be able to replace them fast enough. Ebo Jagers are submersible, and can be placed horizontally along the substrate. Another good alternative is a Titanium Heater. They stand no chance of destroying those.

Plants: Oscars are ground diggers, plants don’t stand a chance with them…….WRONG! Plants and Oscars can successfully be kept together in a tank. When choosing plants for any cichlid tank, it’s a good idea to follow a few rules (not rules, but good ideas): Stick with plants that taste badly to fish, stick with plants that can be tied to rocks/driftwood, and/or stick with plants that are bulbed and can be buried deep within the substrate. Some plants to consider: Bolbitis heudelotti, Cryptocroyne balansae, Crinum thaianum, and Anubias. An Oscar can live anywhere from 10 to 20 years, but it is very difficult in captivity, unless it’s owner provides an optimum environment. Space and lots of it is very important. It’s said 55 is the minimum for one, I say yeah…….but why not go bigger. Cleanliness is also very important if you want to provide the best for your Oscar. They are messy eaters & eliminate huge quantities….that fouls the tank’s water up very quickly. A weekly schedule of maintenance with at least 30% water exchanged will help to keep the nitrates to a minimum.

Breeding: Oscars are egg layers. Both male and female will do a great job at setting up their breeding area, and also taking care of the eggs and fry (once hatched). The male and female will spend time together, following each other about. After such a period of time, they will challenge each other’s strength. You’ll notice a bit of tug ‘o war going on with their lips (lip locking). Tail slapping and rubbing up against each other is also a part of this breeding ritual. All this, and a bond is formed. They will search for a space (preferably flat) to lay and fertilize the eggs. While waiting for the eggs to hatch, they will both guard and fan over them. They are inseparable until the eggs are hatched. And even after the hatching, they will spend time together. Both protecting the fry.

HITH- Hole in the head (lateral line erosion)- Oscars are very prone to HITH. Signs of HITH are usually very easy to see as the fish has lesions on it’s lateral lines, or just above the gill plates. Until treated, the lesions will continue to grow, sometimes causing death. HITH is often called Hexamitiasis (hexamita protozoan) There are a couple theories as to what causes HITH: Absence of a varied diet, presence of activated carbon, high nitrate levels, & poor water quality. I can’t back the Carbon theory up, as I don’t use it. BUT, I can agree that one or all of the other theories can play a role in an Oscar getting HITH. We were newbies, started out with too many fish in a 75 gallon tank. Being newbies, we knew nothing of their feeding and also of the maintenance involved in keeping a clean tank. It was rather cool for my husband and I to see these Oscars devour live feeders…..never thought anything about the feeders possibly being malnourished, or sick themselves. It wasn’t until we stopped with the live feeders, started and continued a regimented schedule of maintenance on the tank, that HITH was no longer a problem.

A couple of other things: Ocellatus means eye spot. On the caudal fin, you will see a spot that is encircled by a brilliant red circle. This is an Oscars eye spot.

Oscars will sometimes fade in color, very drastically. This is a common occurrence if they become frightened. You’ll notice it won’t be too long before he regains his true and darker colors. If he remains dull in color for too long, there may be other things to think about….the fish may be ill.