Crystal Right works by an ion exchange process which reduces iron, manganese ammonia and hardness and can increase low pH all in a single process. The minimum pH requirement is 6. The regeneration process is exactly the same as that used in a water softener and requires regeneration with salt There are two types of Crystal Right. CR100 is used where the pH is over 6 and when the pH is low often increases the pH. CR200 is used where the pH is 7 or above (has a higher capacity). Consult the specification sheet for water quality conditions.