Yes, the positive wire will be the sacrificial anode. It looks like in your setup that it is a stainless steel bracket? Also, what is "Washing Soda" in your formula label? I have good results of using a copper rod, but it is too sacrificial and quickly degrades. Also, the copper rod tend to impart a "copperish" toning to some of my items. It isn't offensive and looks sort of appealing (I might try a common 21 Morgan to "tone" just for effect), but I'd rather find a different type of sacrificial anode.