mcubed

I've got some old granular CYA and it seems as if the specified dosage is not adding to my CYA as it should. I'm guessing that over time (5+ years) that it may breakdown and not be viable/effective. ???

try cleaning the sensors per manufacturer's instructions. if that doesn't work then the sensor is probably bad. try to collect some water from immediately after the cell and test for chlorine to see if the cell is producing. if not, the cell is probably bad.