Oscar
Astronotus ocellatus
The Oscar has a robust, oval body, with a large mouth and prominent eyes. Adults can reach 35 cm. Wild coloration is olive brown with ocellated spots on the caudal fin, but captive varieties (tiger, red, albino) are common. They are very intelligent fish, capable of recognizing their owner. They are aggressive and territorial, especially towards smaller fish. They are carnivorous and have a voracious appetite. Reproduction is classic: spawning on a flat substrate, parents are very protective.
Recommended parameters
| Parameter | Recommended range |
|---|---|
| Temperature | 24–28 |
| pH | 6.5–7.5 |
| GH | 5–12 |
| KH | 3–8 |
| NO₃ | ≤ 20 |
| PO₄ | ≤ 0.5 |
Care
Care notes
A tank of at least 300 L is essential for a single adult Oscar. Ideal temperature is 24 to 28 °C, pH 6.5 to 7.5, and GH 5 to 12 °d. Powerful filtration is needed due to their waste production. They accept carnivore pellets, whole fish, shrimp, and worms. Avoid small fish; tankmates must be large and robust (other large cichlids, catfish). Breeding is possible in the aquarium with a formed pair.