The Weald Aquatics Blog - The Oscar (Astronotus Ocellatus) - another blog post from Weald Aquatics | Aquarium & Pond Fish Shop in Kent


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The Oscar (Astronotus Ocellatus)

Blog post written by Andy | 04 April 2012 | Category: Tropical fish

Hey everybody. It's been great receiving all your positive feedback regarding my last post and it's great seeing so many people interested in keeping Cichlids. I didn't realise how many people kept them already so it's been really interesting hearing peoples' experiences and advice on keeping this fascinating group of fish.

I thought I would start with possibly one of the most popular of all Cichlids... the Oscar!



I would probably say 7 or 8 out of 10 customers will always ask "I would like that big red and black fish down there please. Oh will it go in with my Guppies?" The answer unfortunately is no! They are such a popular fish that we will ask anybody who enquires about them what they are planning to keep with them, and for good reason - Oscars get big and eat fish!!

The Oscar (Astronotus Ocellatus) is a Cichlid native to South America. It is found in Peru, Ecuador, Columbia and Brazil and occurs in the Amazon river basin. Its preferred habitat is slow moving white water with vegetation it can hide in.

Oscars now come in a variety of colours from black and red to pink albinos, red tiger stripes on a black body or a rich copper colour surrounded by dark black fins. They are stunning looking fish with those big eyes and mouths (with almost a slight grin to it).

An adult Oscar can reach a length of 18" and weigh almost 4lbs wherein lies its biggest attraction but also its biggest downfall. An Oscar will outgrow the majority of peoples' fish tanks and can only be kept with large sturdy fish. I usually describe Oscars as mouths with a tail on the end!

Oscars are voracious feeders and will try to eat almost anything they can fit in their mouths. We have had hundreds of horror stories of customers who have bought these fish elsewhere and not been told of their predatory nature, putting them in a community aquarium only to watch their favourite Guppies and Tetras vanish one by one as the Oscars tummy gets bigger and bigger! They do well on a mixed diet of frozen foods and Cichlid pellets but will eat almost anything. Some customers feed adult Oscars frozen mice! Due to their size and diet, an Oscar's home needs to be as big as possible with really good filtration. I think a 3 foot aquarium is the very minimum for a juvenile with the adult moving into ideally a 4 foot tank or bigger. An external filter again in my opinion is essential because Oscars are a messy fish. Regular water changes are important to remove excess nitrates and prevent the build up of problem pollutants that can occur with such a greedy fish. Large Catfish or similar sized Barbs or Cichlids are suitable tank mates but I think they do better in a single species tank.

Oscars like to dig so using larger cobbles or gravel can help prevent this. An Oscar tank can be fairly minimal and decoration with some large rocks (rounded preferably and too heavy to move) or large roots to provide shelter is really all they need as swimming space is more important. Lighting again is not that important but a more subtle light would suit them better. It's is also worth mentioning that heaters have been picked up and broken by an adult Oscar so getting a heater guard is a good idea (most come with them nowadays anyway) to avoid any injuries or the outlay for a new heater.

These fish can live for years and years and develop real personalities - I think an Oscar is the closest you can come to a fish that actually recognises its owner. Customers tell me about hand feeding them and calling their name and having the fish swim towards them. One customer has a 12 year old Oscar that curls around his hand and almost "falls asleep" when he puts his hand in to clean the aquarium! It was in fact an Oscar that got me on my road to fish keeping. My mum (hi mum!) used to take me to my local pet shop when I was tiny, she said I used to sit and watch completely silently as the owner fed the "big fish" in the show tank which would come to the top as he called its name. From then on my mum said I wanted to become a "fish man." My first Saturday job was in that fish section and the rest is history!

Oscars are really fascinating and rewarding fish to keep as long as you have the room and equipment to keep them healthy. It's worth it though because an adult Oscar in a big tank is the focal point of any room! If you want to keep big fish, you really cant go wrong!