I need help! I've stumped multiple hot tub "experts" with this problem and am driving myself crazy!
My hot tub will not hold chlorine, no matter what I do. After putting in the proper amount of chlorine and getting a proper reading (between 3-5ppm free chlorine), within one hour, the reading is back down to zero (for both free chlorine and total chlorine).
Here are details on my levels, equipment and usage:
Hot tub is always covered except when in use. (outdoor tub)
I regularly use shock, typically right after every use. I've tried both chlorine and non-chlorine shock.