Excerpt from "How do I use Bromine in my spa?"
Here is a step by step:
1) On each fill balance the water (adjust TA and pH. Add calcium if below 125 for acrylic spas or below 200 for plaster.) If you have metals in your water add a metal sequesterant.
Calcium: Is the target 125 ppm?
(APSP range is 100 - 800 ppm. Ideal 150 - 250 ppm.)
Sequesterant: Our hot tub manufacturer recommends adding a sequestering agent once a week as a stain and scale controller. I am wondering if that is a blanket statement for warranty purposes because they do not know where their hot tubs will end up. My water out of the tap: Copper 0 ppm, Iron 0.1 ppm, TDS 200 ppm. The last time I used the Manufacturer's sequestering agent there was an increase in foam and a de-foamer was recommended. I found several one time sequesterants online. Is there a recommended brand? Once or weekly? Do sequesterants prevent scale build up?