Regeneration: Purigen® can also be regenerated. As it adsorbs waste products, Purigen® will change color from a pale blonde to a dark brown, almost black. Once it is exhausted, it can be regenerated with a solution of bleach and water. The bleach will literally “burn off” the organics that have been removed from the tank. Watch out for products that claim to be regenerable with a brine solution. That is the regeneration procedure for ion-exchange purposes. A brine solution will not remove organics. While such resins have a limited capacity for organic adsorption, a brine regeneration process only replaces removed ionic compounds. It does not destroy large organic molecules that were removed, which is the primary function of organic adsorption resins.