These units have an unusual feature in that they have a replaceable cartridge that spits out small silver/copper particles allowing the chlorine levels to safely fall to .6ppm (so they claim). Probably the same technology available in several washing machines you may have heard about. I have been running this unit for a year .... certainly have had no problems balancing and opening this year was a breeze.
The cartridge is supposed to be replaced every year ($99) or the chlorine levels need to be bumped up to the 1-3ppm level.
Any one else running this units and decided if the yearly replacement if worth the effort and cost .... i suppose if anyone were really sensitive to chlorine they would be happy to!