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As the title says I am having a light yellow appear in my hot tub. It opticaly looks just bellow about a foot of water, it is very light yellow in what otherwise appears perfectly clear water. We are using the baqua spa system for that it is worth. all the levels appear to be dead on with about 30 to 40 day old water. I do have a strange issue my PH likes to creep up for little to no reason from time to time i am not sure if this is related to it or not. I have about had it i am pulling my hear out i can not figure out what could be causing this strange chemical reaction, there is no odor emanating from the water ither. Any thoughts would be greatly appreciated