Friends I am using this product for last 5 years.It has sufficient amount of water filter quality and baterry adds good amount of mineral into it.But friend many times it got ant into purifier.May be ant get attracted toward water tastes.Battery change will cost you 500 to 600. Rupee.i have change is 6 months. And friend it filter water not purify.for purification we require a RO and UV system.charcoal at top removes colouring substance, middle batter add mineral and lower bottom removes other particles from water.