I HAVE BRASS ELBOWS AND T’S USED WITH MY POLY B PLUMBING. THE PIPES HAVE BEEN IN FOR 11 YEARS AND WHEN TURNING OFF MY HUMIDIFIER I NOTICED A GREEN BUILD UP OF CORROSION ON SOME OF THE CONNECTIONS. BOTH COLD AND HOT — NOT ON ALL JOINTS — WE HAVE A WATER SOFTENER??? CAN ANYONE OFFER AND SUGGESTIONS? HAS ANYONE EVER SEEN THIS PROBLEM?