Too many times we go into fish stores and see little balas of 2-3" for sale in tanks with tetras and other small fish. They get bought by people who don't know any better and it's a shame. It's pictures of fish like yours that need to be in stores showing the potential size that some of the fish can achieve.
You can take some comfort from the fact that you had it in a very large tank and it had 9 years of a good life. But still, I feel for you man.