It’s a matter of long-term economic effect. Both work, but one is cheaper in the long-term because bromide sanitizers for longer at higher temperatures, such as those which exist in hot tubs. That’s the point they were making.
Chlorine also works fine, but because of the higher temperatures, you have to use more, which cost more.
And you won’t, if you add it more frequently.
It’s a matter of long-term economic effect. Both work, but one is cheaper in the long-term because bromide sanitizers for longer at higher temperatures, such as those which exist in hot tubs. That’s the point they were making.
Chlorine also works fine, but because of the higher temperatures, you have to use more, which cost more.