Now I remember last year. I was maintaining the recommended calcium level in my Intex/SWG pool and I had a terrible time with calcium carbonate packing up the electrolysis cell. Had to soak it in HCl plus some scrapping with a thin piece of plastic to get the cell cleaned out three times. I wonder if those calcium carbonate deposits could short out the cell or at least reduce it's ability to create chlorine from chloride.

Richard