Oscars have been my favorite fish since I was a young boy and I’ve raised several of them to adulthood, mostly in large tanks…
The largest I’ve ever raised is 13.5” (TL). This fish was around 2 years old and 12” when I received her. She was raised in a 90 gallon and has been in my under stocked 300 gal for the 5 years I’ve had her.
The largest I’ve ever seen was 14” and was 10+ years old kept in a 500 gal display tank at Critter Pet Shot in Allen Park Michigan… but this was many years ago…
If you play on Google you will not find any verified records of an Oscar any where near 22”… nor even 18”… If anyone truly has a fish this large then you have the largest Oscar in recorded history… verify your claim and have your fish noted…
I personally do not believe that an Oscar will exceed 16”, and even that is exceptionally unlikely…