his comments are total BS.

He may truly beleive what he is telling you or know better is simply trying hard not to lose an accont that is worth $500 a year.

Chlorine is chlorine. Lith or Calcium or whatever is simply the medium to keep it stable to get it into the pool. Bleach does the same thing at a fraction of the cost.

Get a cooler of beer, sit in the sun and think of yourself there without the beer or the pool supply guy in his yard drinking it for you.