This reason most oscars (or any cichlid for that matter) don't reach their full potential in aquariums is that they are kept in "too" small tanks, where nitrates and other toxins build uo quickly, and have a stunting effect.
In a 75 gallon tank nitrate will build up twice as fast as a 150, etc etc.
And if a water change is done once per week or once every 2 weeks, it means the oscar is swimming in a nitrate soup, so no wonder an average captive oscar stops growth at 12".
In nature oscar live in waters where nitrate (due to natural processes, may be < 2ppm, and the million gallons of water that surrounds them is changing every second. (the average flow of the Amazon rive is over 7 million cubic feet per sec, there are 7.5 gallons to every 1 cubic foot of water).
A 75 gallon aquarium is a puddle for any fish over 7".
In a 75 gallon tank nitrate will build up twice as fast as a 150, etc etc.
And if a water change is done once per week or once every 2 weeks, it means the oscar is swimming in a nitrate soup, so no wonder an average captive oscar stops growth at 12".
In nature oscar live in waters where nitrate (due to natural processes, may be < 2ppm, and the million gallons of water that surrounds them is changing every second. (the average flow of the Amazon rive is over 7 million cubic feet per sec, there are 7.5 gallons to every 1 cubic foot of water).
A 75 gallon aquarium is a puddle for any fish over 7".
