Please read this article on the proper bonding of swimming pools. As we have many fiberglass pools, which no longer have metal hand rails, ladders, or lights, this is becoming a common issue.
The code requires bonding of the pool water. If your swimming pool, especially a fiberglass pool (like San Juan Fiberglass Pool) isn’t bonded, your water is not safe to swim in and it will cause issues when removing metal stains.
Water Bonding Article From The Edge 2nd Quarter 2018
If you are using doing a stain treatment and using a CuLator Ultra 4.0 and the contents of the bag do not change color and your stains come back right after you chlorinate, then you either have a bonding issue or iron bacteria.
Call Periodic Products at 954-764-7654 to review.