Hi everyone. I know! Long time since I posted. I need some expert advise please. I have a fresh water tropical tank with mini reef system. Instead of using plastic for the weir guard I decided to use Galvanized Tin (Gutter Guard for house roof gutters). Over time, this metal has rusted & deteriorated. the $64,000 question is....would this be causing Tin poisoning in my aquarium? Merry Christmas & Happy New Year! :;shat Regards John.