What's the real difference between reptile and fish tank water conditioner?

Reptile water conditioner usually contains chemicals such as Water, Dechloraminating Agents, Synthetic Organic Polymers (Colloids), Chelating Agents, Electrolytes. The reptile conditioner usually also has a chemical that binds calcium in the water as well as a slime protecting agent that is good for amphibians and fish. Aquarium water conditioners (for fresh water fish) contains chemicals such as sulfates such as sodium thiosulfate. Thiosulfate is a Redox reducing agent. Either should be ok for reptiles or fish, however I would stick with reptile conditioner for reptile tanks or mixed (reptile and fish) tanks and for aquaria with fish only I would use specific aquarium water conditioner. The main reason to use a water conditioner is to remove chlorine in water. This, however, can also be attained by leaving the aquarium water fresh from the tap sitting over night. The chlorine will dissipate.