Ideal Drinking water from reverse osmosis..

Ideal Drinking water from reverse osmosis, distillation, deionization, microfiltration, etc..

0-50 PPM

Often considered acceptable range for carbon filtration, mountain springs or aquifers.

50-140 PPM

Average tap water.

140-400 PPM

Hard water.

170 PPM or above

Less desirable

200-300 PPM

Unpleasant levels from tap water, aquifers or mountain springs.

300-500 PPM

The EPA’s maximum contamination level.

500 PPM