I have a spectrapure MPRO 25 and it has a blue and a yellow water OUTPUT lines coming out. WHICH one is the good water and which is bad. My guess is that the blue is good and yellow is bad. ALSO does anyone know where to get replacement filters for these mail order? Someone told me that KENT are interchangeable with spectrapure? Is this so? I have moved to an area with lower water qualities and have lost my GOOD water contact.