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The ONLY chlorine that is suitable for a Hot Tub is Di-Chlor which is granular and administered daily when needed, all other chlorines are verbotten in a Hot Tub. Your sensitivity problems are the chemical stew you are sitting in. Tri-Chlor is 2.6 on the pH scale, and liquid chlorine is 13.0 on the pH scale. Both are POOL CHEMICALS and are not suitable for Hot Tubs. You skin is pH neutural 7.2 to 7.6 range and the sensitivity reaction is chemically induced on the bather.Dump the Tri-Chlor, get an ozonator, and use granular chlorine as needed.