Filters don't last.  The first set worked great and lasted 6 months before needing replacement.  The second set didn't even last 2 months and water flow was just trickling.  However, the light indicator still has 75% life left.  The 3rd set was even worse . . . .literally watching water drip.  But the filter changing light is full.  What is the issue?  Should I waste more money and buy another set for it to last one and a half months?