After using SpaBalancer, the filters are dark brown. What is this and what can I do?

Filters can often turn brown when SpaBalancer is working in freshly filled water. The brownish discoloration may be from excess calcium or metals dissolved in the water, such as iron, copper or manganese.
Soak the filters in cleaning solution overnight. The next day, rinse the filters thoroughly and then soak them in chlorine solution for another night. This will cause the filters to bleach out, giving them back their white color.