HACH Hardness (Total) Test Kit, Model HA-71A, Drop Count Titration, Dual Range, 100 tests: Product #: 145201

Hardness:

• Water hardness is caused almost entirely by calcium and magnesium ion. Other di- and trivalent metals have a similar effect, but usually are not present in high enough concentration in potable waters to cause problems. Hardness increases soap consumption in laundries and causes scale in boilers.
• Simply count the number of drops required to change the solution color to determine hardness concentration.

Method / Chemistry	Range	Smallest Increment	Approx. Number of Tests	Case Style
Drop count titration/EDTA	LR:1-20mg/L	1mg/L	100	8.8x6.5x5.8 inches Blue Polypropylene Carrying Case
	HR:1-20 gpg*	1 gpg

* 1 gpg = 17.1 mg/L