[slap bash]

I a have often heard the question of when is my RO come to the end of its lifespan, The correct answer is when a  RO cannot reduce you TDS to 10%  of the taps TDS THEN ITS SHOT. EG My Tap water is 310 TDs  so my RO when is good working order should produce a  TDS of 31 or less.
Now when its reaches this point `chuck it yet it will still work. But understand you di will be working harder and more costlier to produce pure.