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This page will give a completely detailed profile of the selected fish, from A to Z. The profiled fish will be chosen randomly by Badman, and will come from the complete genre of tropical fish. New profiles are added on a regular basis. If you would like to submit a profile for the site please contact me. Don't forget to let us know you experiences with this fish by filling out the




Astronotus ocellatus



    Perhaps the most commonly seen cichlid the oscar is always available. Seen when small most shops fail to note its' size potential and the unaware new hobbyist comes home with a fish that quickly outgrows all but the largest tanks.

Quick stats:

    Listed tank sizes are the minimum
    Size: 13+ inches (30+ cm), Same for both sexes
    Tank: 55 gallons for young 125+ for adults
    Strata: Mostly Middle, will visit all levels
    PH: 6.5 to 7.5 (neutral)
    Hardness: Soft to hard (dH: 5.0 - 19.0)
    Temperature: 75°- 86°F (24° to 30° C)


    Order: Perciformes
    Suborder: Percidae
    Family: Cichlidae
    Genera: Astronotus

Common name

    Oscar, Tiger Oscar, Velvet Cichlid

Image gallery:
    Additional species photographs


    Badmans' Forum


    Amazon river and its' tributaries also Paraguay.

General Body Form
    Oval and elongated when viewed from the side. Very robust body. Dorsal fin starts above the gill slits, Caudal Peduncle taller than long, Pectorals and unpaired fins rounded and Ventral fins are pointed. They can reach a size of up to 14 inches and are sexually mature at around 4 inches.

    Varies greatly, very pretty and is different between individuals and age. Background color of mature specimens is dark Olive Green, Brownish Black or Blue Black. This pattern is broken up into large random spots and black band edged with pale White or Yellow. The Dorsal fin can have a few eye spots and males may also have three small Basal spots in the spiny portion. The Caudal fin can have Red-Golden spots and a very jet Black spot edged with Red at its base. The wild form of Oscars have been selectively bred to include many beautiful varieties including the Tiger, Albino, Red Tiger and more.

    The Oscar is one of the Easiest fish to care for and for its size one of the most peaceful. The tank should be large-at least a 55 gal with a medium textured substrate. Keep plants to a minimum and provide flat rocks and pieces of driftwood for cover. If you want to use plants I suggest large leaf varieties of lilies or some floating plants, Oscars like most Cichlids can and will dig the substrate. Water conditions for Oscars are not critical but they do like medium hard, Acidic to slightly Alkaline ( pH 6.5 to 7.5 )water. Feeding as you would expect is no problem as oscars will take all types of food including flake frozen, pellets, kitchen scrapes and of course live. Do not restrict your Oscars diet to feeder goldfish as these do not provide all the needed nutrients, in nature they are an opportunistic fish and will eat anything that happens by. I even dig Earthworms from my yard for them. Oscars are a very long-lived fish and quickly develop their own personality, probably one of the reasons they are so popular today.
Tiger Oscar

    Oscars will form true pairs and stay together for the duration of their life, each take part in the laying of the eggs and caring of the young. The Oscar is a typical open brooder. The eggs are colored to match their environment and adhesive and are laid in the open, on a rock or a large leaf. They can lay a large number of eggs. The Hatched fry are looked after and fiercely guarded until the egg sac is absorbed and the young are free swimming. Parental care extends even beyond this point in the form of protection from predators. This phase is very dangerous for other fish in the aquarium as the parents can extend their brooding territory and increase their aggressiveness.

Your comments:


Please remember that the following comments are personal experiences and may or may not apply to your setup. Use them as guide to help better understand your fish, like us all individuals will behave differently under different circumstances.


From: Debra A.
I've raised oscars off & on for over 20 yrs. Always only had 1 at a time in 100 gal tank. 3yrs ago I got 2 baby red oscars less than a inch long. they were great w/each other until they got about 10 inches long. larger 1 was very aggressive almost killed each other, separated them finally gave away aggressive 1 . mellow 1 I keep w/pink squirts,guppies, feeder goldfish,white clouds [does not try to eat].. however aggressive w/14inch pleco ,but swims together with raphael cat fish go figure that out! goes to show all different personalities of a oscar fish Thai's why I like them
From: Melissa
When I was growing up most of my life my parents always had tiger oscars and as my brother got older so did he. When I got my own fish tank 2 years ago I bought 2 tiger oscars from the pet store, I paid $10.99au for each tiger oscar. I was so proud that I too had my very own tiger oscars. I have a 5ft long by 2ft deep by 2ft wide tank so they have room to swim and grow big. My tiger oscars have never been aggressive towards other fish or to the fresh water snails, til one night I noticed that my oscars were hovering over a section in my tank. Their I noticed that their were over a 1000 eggs been laid. I also noticed that my two oscars had become aggressive to the other fish and fresh water snails in the tank. I have never bread tiger oscars and I had to phone my dad for advice on what to do as he has bread tiger oscars before, he explained that it is a hard thing to do and itís even harder to get a pair of baby oscars that have grown in to a breading pair. So I went on the search on the net to read how to do this so I get it right the first time and I have lots of tiger oscar eggs hatch. I have all the right environment going on and I had to remove the other fish and fresh water snails and since doing so my pair of oscars have settled down there not aggressive any more. To sit and watch my pair care for there eggs and fan the water around is one thing and then I saw my male oscar do his job. My oscars I thought were acting strange and after reading up on it I have come to understand that there doing every thing right. It is truly a wondrous thing to see and to be able to watch my own oscars is amazing and I truly am enjoying the experience.
From: Aaron Godden
My girlfriend and I bought a pair of oscars about 6 months ago and put them in a 2x2 tank but pretty much straight away got our hands on a 6x1.5 to give them some space. Since then we've both become obsessed with aquaria and cichlids particularly and it's all thanks to our oscars amazing intelligence and personality. They are currently living mostly peacefully in the 6ft and have a 4" jack dempsey, a 1" jack dempsey, a 2" red devil and some bristle noses and clown loaches to keep them company&aside from the odd scrap over space as well as the occasional missing smaller catfish we haven't had many problems with aggression at all considering. The only problems occur when attempting to feed them meat pellets or other standard pellet food in which case they usually start throwing tantrums and getting nippy towards each other but all in all i personally believe that aggression and even so called 'standard' behavior all comes down to the fish themselves as well as numerous variables. Our male is around 60% larger than the female now(he's about 20cm)and recently he was getting nasty towards her but it only took about 45mins to train him that if he bites her,the net goes in the tank!
From: SuperCichlid21
My experience with oscars in regard to other fish is that you can do it as long as you give the other fish plenty of space. Right now I have 2 12in oscars (both tigers), in a 200 gallon breeder tanks (breeder tanks are the tanks that are half as tall but twice as long to increase surface air exchange). I have found other large cichlids such as Dempseys,Manguanese, Green Terrors, and even Red Snooks do quite well with oscars. Right now my Oscars are sharing their tank with an 11in Jack Dempsey and a 9in Maguanese. The have been living as such for a little over 6 years. I have also found that bottom feeders such as plecos do all right with Oscars. The key is proper introduction, to make sure that the new fish is experiencing as little stress as possible, similar sizes, and adequate foods. If I were to give my oscars less food then they are receiving now then they would fight each other and the other fish as most animals do when there is less then the accustomed amount of food. This is not to say that over feeding them is okay but if you make sure there is no real hunger then territorial fights will be kept to a minimum. Also note that it is much better to have a few fish that receive optimum care than many that will only receive minimum care. DO NOT force fish on to each other. Just because others have had luck with certain species combos does not mean that all fish will accept other species. If you notice real aggression, separate them immediately. It will both stress out your resident fish and may damage or kill your new fish if you allow them to remain together. Also make sure you research the fish's requirements. If you introduce them slowly and carefully though, and make sure they're of similar size, temperament and requirements, I truly believe that you can keep oscars with other fish.
From: Lochie
I have had my two oscars for about 6 years, I have a tiger and an albino and they are both around 20cm. They grew up together, and now are inseparable. I keep them in a 150ltr tank, but have outgrown that, so I have just bought a 6x2x2 foot tank, to give them that extra space to stretch out there fins! As they love to attack lots of things in the tank, I recommend a heater guard and fake plants, as they love to uproot plants anyway. To stop your fake plants from floating to the top of the water when attacked, silicon some large pebbles or stones to the base or anchor of the plant, to give more weight. They are extremely messy and fussy eaters, so make sure you over compensate your filtration. I wouldn't recommend under gravel filters, as oscars love to dig in the gravel, under gravel plates can often cause some damage around the mouth and gills. In my new tank, I am using two large canister filters, both do 1200ltrs of water an hour, and two 300watt heaters. As they produce a lot of waste, filtration is number one. As long as you have a good bio system in your tank, ammonia and nitrate levels will remain at safe levels. I love my oscars, and can't understand how people can give them back to pet shops, just because they get to big, If you buy a oscar, be prepared to buy a big tank, and do your research because they do make great pets, but not if they are unhappy. If you want to keep oscars with other fish, be warned, Oscars, like most cichlids, they are highly intelligent, there is no guarantee that they will get along with other fish, it may work, it may not, at the end of the day it is up to the fish to say who stays and who will go.
From: Becky
Oscars are hands down my favourite fresh water tropical fish to keep! Best raised in larger tanks as young fish with plenty of space to allow rapid growth with correct diet. They often see other fish as potential food or rivals so best to keep a monospecies tank. Very entertaining fish to watch with at times odd behaviour and destructive aggressive fits taken out on other fish,equipment or even the tank itself. Very hardy and fairly low maintenance but if cared for with clean living conditions disease is minimal with the odd self inflicted injury sustained from head butting and scratching behaviour. Live food is clearly the best diet although quality pellet foods are often a good supplement.
From: Adam
I have had peaceful Oscars and aggressive Oscars. You won't know which you have until you get to know it. Certain varieties are more aggressive then others. Pink Oscars are very laid back. I read that Tiger Oscars are the most aggressive of the group, but I have found that this is not true. My common Oscar (AKA Zebra Oscar) picks on my Tiger Oscar constantly. He also harasses other fish to death. So far he has killed one shark catfish, Black Ghost knifefish, and even my new barracuda. The knifefish and the barracuda were bigger than my Oscar. I've only had this Oscar for a month! He has tripled his body size in just 4-5 weeks. I feed them Cichlid Gold pellets in the morning, high quality flakes in the afternoon, and bloodworms in the evening. I give them a bedtime snack of the pellets. They eat feeders only once per month. Remember, if you want you Oscar more docile, feed it less protein and more plant matter (like what is found in tropical fish flake food). Also, Oscar's should not be kept in a tank smaller then 70 gallons. The general rule of thumb for fish is one inch of fish per gallon. Because of the waste they produce, it is recommended that Oscars have three gallons of water per inch of fish. If you have two five inch Oscars, you have ten inches of fish all together. Ten inches of fish times three gallons of water equals a tank of at least thirty gallons. Most Oscars will reach a length of 10-14 inches when fully mature. If you have two fish that are twelve inches long, then you have 24 inches of fish...times three gallons of water per inch...equals a tank of no less then seventy-two gallons. Some people can keep their Oscars with other fish much smaller then the Oscar. Just remember, even when they are raised together, the Oscar may still eat it eventually. Lastly, Oscars must not be kept with "community tank" fish, unless you want them to be eaten. Just because the Oscar is too small to eat them doesn't mean he won't chase the fish (sometimes to death). I adore my two Oscars. I have a five inch Tiger Oscar. The funny thing is that it doesn't have ANY orange on it. It is gray/black. Very cool. My common is about four inches and is the leader of the tank. He gets so excited when he sees me get close to the tank. Regarding feeding, I don't suggest buying feeder fish of any type from a pet store. Unless you plan to quarantine the feeders they will, eventually, give diseases to your main tank. I suggest breeding guppies. I have a three gallon with three guppies. I also have a batch of one week old fry. Oscar's are prone to hole-in-the-head disease, but you can buy a preventive at your LFS.






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