| I know some bottled water companies will do a full test of your water. Also, your local government has to periodically test the tap water and publicly divulge those results.
To do some elementary testing, try mixing some saltwater using tap water and then use a nitrate and phosphate test kit. Another thing you can do is use a TDS meter to measure the total dissolved solids in the water. My tap water's TDS is a bit over 200, while out of my RO it is zero... that says a lot IMO. |