Oscar
Astronotus ocellatus
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A fish with real personality, Oscars should be placed in large aquaria when young and given very frequent water changes to avoid health problems
Overview
Synonyms | Lobotes ocellatus, Acara compressus, Acara hyposticta, Astronotus ocellatus zebra, Astronotus orbiculatus |
Distribution | Native to Argentina, Brazil, Colombia, French Guiana, Paraguay, Peru, Uruguay & Venezuela. Introduced to many other countries. |
Maximum Size | 34cm |
Temperature | 23-27°C |
Water Parameters | Will acclimatise to a wide range of conditions. pH: 6.0-8.0, dH: up to 25 degrees. |
Compatibility | Non-Community |
Lighting | No special requirements |
Sexual Dimorphism | Difficult to distinguish unless a natural pair forms within the aquarium. |
Feeding | Cichlid pellets, flake and frozen foods Cichlid pellets, flake and frozen foods |
Description
Care
The Oscar is a very large-growing South American cichlid that will eventually require a very large aquarium. Juveniles can be kept in smaller aquaria, but they are fast growers and will need moving to bigger quarters fairly quickly. They are NOT suitable for housing in a community situation, as smaller fish will be preyed upon. These cichlids will have individual personalities, but they do usually make good companions for *appropriately-sized* large catfish such as the Common Pleco (Pterygoplichthys pardalis), many of the larger-growing species of Synodontis or Pimelodids, large talking catfish and so on. Ideally, the tank will be spacious enough to house at least 5 or 6 specimens, as smaller groups can result in aggression-related problems, whilst a solitary specimen, on the other hand, will become lonely and withdrawn. The only exception to this rule is when re-homing a compatible adult pair, as they are unlikely to accept newcomers into their domain. The tank itself should have a large open swimming space and some robust décor at the sides and back. Be sure that any rockwork is very secure, as these fish can be fairly destructive and like to move things about "“ falling rockwork could have disastrous consequences. Plants will be uprooted and damaged, so they are not recommended. Heaters can be easily damaged, so ensure that they are fitted with a proper heater guard, or else use a filter with a built-in heater, or place the heater inside a sump. Ensure the tank is well-covered, as these cichlids are capable of jumping. Oscars not only grow to quite a length, but attain a large body mass too. As messy feeders they require an excellent external filtration system, coupled with frequent partial water changes to cope with the amount of waste produced. If excellent water quality and proper diet is not maintained, this species is susceptible to hole-in-the-head disease, and this really can be so easily avoided. Many Oscar keepers report how these intelligent fish quickly learn to recognise their owners, likening them to "pet dogs", such are their characters and responses to visual stimuli.Several varieties exist including Albino, Red, Red Tiger and Long-fin.
Feeding
Foodstuffs should be tailored to the size of the fish. Smaller specimens will enjoy frozen foods such as mosquito larvae, brineshrimp, Mysis shrimp, "cichlid-diet" etc along with flake and slow-sinking pellet foods. Larger specimens should be offered bigger frozen foods such as krill and cockle, plus chopped prawns, mussel, whitebait etc plus sinking cichlid pellets. There is absolutely NO need to offer Oscars live feeder fish and we do not encourage this practice in any way. Aside from the ethics, there is also the risk of introduced disease. Oscars are in no way picky feeders and will avidly consume pretty much all prepared aquarium foods with gusto.Breeding
A compatible pair that are ready to spawn will clean a flat horizontal piece of decor (such as a large piece of slate) in preparation for the event. Several thousand eggs will be deposited onto the pre-cleaned area and are guarded by both the male and female. The eggs usually hatch within 72-96 hours, dependant on temperature, and not long afterwards, the parents will move the young into a small pre-dug pit.Where can I buy these aquarium fish?
If you like this species and would like to find out more, we have an enormous range of aquarium fish and invertebrates available to buy in all of our stores across the UK (including freshwater tropical and marine fish).
However, please note that this species may not be available in your chosen store, even if the store specialises in this particular species. This is due to seasonality and stock availability from store-to-store. Please check with your local store about availability of specific species to purchase before making a journey.
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