To me, as long as you're drinking a bottle of water with it I see no harm. You get hydrated from coffee. Of course you need to drink water in general, but the concept of drinking cups of water to balance out dehydration from coffee is just a myth.
Reptiles do not maintain their own body temperature within a narrow range like mammals and birds, so controlling their environmental temperature is critical for normal activity and good health. Reptiles are poikilothermic-which means that their body temperature alters with the surrounding environmental temperature.
The tank can be kept at room temperature, though during heat waves it should be moved to a cooler room, such as a basement. Health Concerns: Like frogs and other amphibians, toads have specific dietary and environmental needs that, if not met, can lead to lethargy, illness, vitamin deficiencies and even death.