I freshly filled the spa and added SpaBalancer. The water has turned a milky color. What is this?

This reaction is normal. SpaBalancer starts working and encapsulates contaminants in the water. This is what causes this discoloration. It is especially common and intense in spas that have been in service for a while. Biofilm has formed in the pipes there. SpaBalancer dissolves this biofilm.
Please clean the filters the next day and extend the filter runtime.
Normally, the cloudiness will have disappeared by the next day. In some particularly severe cases, the water may be cloudy for up to three days.