Yes, as was said earlier in the thread - Discovery Cove offers 3/4 wetsuits that should keep you warm.

As for the tempterature in the pools, they remain constant throughout the year. The fresh water Resort Pool and Tropical River are maintained between 86°F ±2 degrees (30°C ±1) and the salt water Dolphin Lagoons, Stingray Lagoon and Coral Reef are 77°F ±3 degrees (25°C ±1). So the water should be just as warm as it is in July!