How to refurbish my glass aquarium?

40-gallon aqaurium sat outside for about a year. Glass is foggy, and seems to be baked in to the glass.

Looks better after we scrubbed with diamond dust, but is still not perfect.

Any ideas on how to get it back to new. We already tried CLR and a couple other acids on small spots. The only results we’ve gotten is from razor scraping and diamond dust.