No, just raise the water level to at least 8" up to 24 inches above the soil, The roots and tuber do not need to be exposed to the sun, they will benefit from being deeper and allowing the pads to climb up to the surface.
A water temp over 96 will not affect them adversely but you must remember, the warmer the water the more fertilizer they will use, warm water and fertilizer = high vigor.
Cheers,
Sean