OK, I've had my HS Envoy for over two years and just experience chlorine lock for the first time. My FC levels have been around 5 ppm for the last week or so. Typically my FC levels are almost zero the day after I soak. I haven't added any dichlor for the last few days. I'm using N2 with ozone. I use about a teaspoon of dichlor per user after each soak. This has worked out well in the past.
Anyway, should I let the levels minimize before I add any more chlorine? My water is about three months old. I'm thinking I should probably dump the water at this point. What causes chlorine lock?