I looked on the web site but didn't see a schedule. You may be out of luck because day light savings time ends on Oct 27th, so it will still be light out by 7pm. I'd have to guess that the fireworks end after the 1st week in August when the park closing hours change.
It is a nice show, and worth seeing close up, because like gschmerl said, they have effects in the lagoon. Some of the fireworks are on poles that spin and sway. Other times they shoot across the lagoon like a battle. The music is part of the show.
I've seen it twice this year at IOA, and my dad said it was one of the best firework shows he's ever seen, I agree.
Then as you leave IOA, you see the fireworks from Universal going off.