Chlorine
Chlorine is the most popular choice amongst hot tub and swimming pool users for sanitation.
It's very easy and fast to dissolve and so works quicker than bromine in all water types.
Chlorine is also cheaper to buy and gives the water a clearer and crisper look, water with Bromine can look a little dull by comparison.
The downside of chlorine is the strong scent it gives but this is usually as the water is not clean (e.g. public swimming pools) and it is harsh on
sensitive skin types.
Unlike the dispenser which lets you monitor who much Bromine is required, chlorine needs the use of testing strips and is more chemical based