tank size for oscar cichlids

Question
Hello,
I have a 29 gallon tank currently holding one eight inch oscar cichlid. Now I know you might say this is WAY too small for even say a three inch oscar. But, I have read in a VERY good fish
book called, "the simple guide to freshwater aquariums" that ONE oscar but only ONE and no other fish or creature can live in a 29 gallon provided that 50% weekly water changes are made.
The Author of the book is very knowledgeable and
raises oscars himself. He has kept fish for over 50 years.

We change the water in our oscar tank 3 times a week with each size of the water changes about 30%
to 40% each time. I am careful about feeding and am right on top with filter maintenance which in
case you needed to know the filter is an TOPFIN 30
powerfilter. The water temperature is kept at 80
degrees farenheit. Our oscar is always swimming around and looking for food he has very nice color
and he apparently seems very happy in his own 29
gallon tank. My question is what is your opinion
on what I said above, whether you think an Oscar
can live in a 29 gallon provided that massive and
frequent water changes are made.
I feed my Oscar Hikari cichlid pellets, Krill,
Shrimp pellets, Tropical fish wafers, sometimes flakes. NEVER, EVER feeder goldfish for the Hole in the head and other disease risk.

Thank you for your opinon,
sincerely,
Susan*

Answer
Hi Susan;

Wow! I wish I could get every hobbyist to keep their tanks that clean! You are doing a fine job. If your fish seems happy, I wouldn't change a thing. Most people let their tanks get pretty dirty and a smaller tank like yours would become a death trap for their fish. Keep up the good work!

Followups welcome.

At Your Service;
Chris Robbins