Im going to start this off with, "I dont keep shrimp".
People often treat ich in tanks by raising the temperature to 30c/86f for a couple of weeks, especially when they have inverts in the tank because ich medication will kill inverts.
When we've had heat waves here in the UK, ive had tanks in the high 20s for weeks on end, and this year above 30c for a few days. We dont normally have AC
here, so rooms tend to get warm when the weather is warm