Dear Sirs,
I am living at Anantapur, Andhra Pradesh, where the underground water is hard.   In the market the water softening plants are more expensive.  I want to assemble a water softener for my personal use. So, I request you to intimate the chemical name of the Softening Resin, which is used in water softeners.

Thanking you,
Yours sincerly,

D. Narendra

dunari123@rediffmail.com