Accu-Tab® W8000134 100 lb Calcium Hypochlorite Wastewater Tablet Pail. Accu-Tab® three-inch calcium hypochlorite Cal hypo tablets are able to erode reliably, consistently and predictably because they undergo a multi-step manufacturing and quality control process so they will not soften and clog the system - a common problem with knock-off three-inch tablets and briquettes. Accu-Tab Wastewater tablets are for use only in small-scale aerobic wastewater treatment chlorinators. The patented tablets do not contain stearate that can be highly reactive and instead contain Hi-Sil® H-303 silica, an erosion modifier from PPG Industries engineered to provide a steady source of chlorine.