I have been told by a chemist that the reverse osmosis filter yields water as pure as distilled water.
That's quite far from truth. With good feed water a sinle stage RO will deliver a purity somewhere between 17 to 20 uSiemens. A two stage RO should bring that down around 8 to 10 uSiemens. Distilled water has a conductivity around 1 uSiemens.
Those results are with industrial RO systems, them 'under the sink' ROs will never get near theose figures.
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