Who knows oscars?

Yikes!

I will add my two cents to this and agree with the others.

55gal is the min requirement but larger is better for oscars. It's terrible to think this kind of info is still being passed around and these poor fish will suffer.

Also, big kudos to you for even taking the time to go to the library and read up about this but I'm just really sorry that the info you got was outdated and completely false.
 
I think you should send a letter to the author of the book to find his opinions on this, and tell him yours.

it is a myth that they grow to the size of the tank. a healthy oscar will keep on growing, no matter what size tank he's in, but an unhealthy oscar will be stunted and die early, because what stunts the fish is ammonia posioning. because they make too much waste for the small tanks filter to handle, they posion themselves with ammonia, which retards their growth.
 
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