Chlorhexidine or Nolvasan for Tub Cleaning (disinfecting) )

[kc261]

What's the difference? Is Chlorhexadine a generic Nolvasan?
I can buy a gallon of Chlorhexidine for around $22.00 and Nolvasan costs about $60.00.

I believe Nolvasan is chlorhexidine diacetate, and most of the generic chlorhexidine products are chlorhexidine gluconate. I have no idea what this means in terms of its safety, effectiveness, etc.