What's a good manufacturer of Dichlor granules, and where can I buy it?
The last time I purchased Dichlor at Home Depot (or was it Lowe's, I forget which) there was a new shipment that had just arrived. I selected a jug from this batch but I've discovered that it's extremely weak. Don't know if it's the chlorine itself or the lack of cyanuric acid. I've watched my spa's free chlorine go from 5 ppm to 0 ppm in one day's time, and that's in recently shocked water, with nobody using the spa. The DE filter was recently cleaned as well, so I can't explain the chlorine demand any other way.
FYI, the brand name is "Pool Time" aka Aqua Chem, which is an alias for Recreational Water Products (Chemtura).