I have three 200 gallon boxes of Reef Crystals(used last two years) to go through before I can make a change to Instant Ocean(used first year and a half).
If the Georgia Aquarium uses Instant Ocean then I would feel comfortable with my Reef Crystals or Instant ocean.
"We use instant ocean to create our salt water. It actual comes as 2,000 lbs bags of salt mixture that we add to water in special holding tanks. We use Instant Ocean synthetic salt for all our saltwater systems, including reef displays. We regularly test a wide range of water quality parameters and make adjustments/additions to each system according to each exhibit's specific requirements."
I still forget the benefits of using Instant Ocean over Reef Crystals.