i bought something similar a few months ago for brewing - was a 7 gal aluminum crab pot. ive noticed a very slight metallic smell to my first two brews that ive done. the smell is right when you put your nose up to the glass for a gulp. i dont taste it, just a slight smell. ive tried researching to see what this smell is, and the aluminum is my only conclusion..... for now.
i did not boil water in the pot before my first brew. for my second brew, i figured that since i brewed with the pot already the pot would have a layer of oxidation on it, but i still find the smell in my second beer. just brewed my third batch this week. i boiled the sh!it out of that pot before brewing and got a nice black oxidation layer going on now. we shall see in about 5 weeks whether that was the problem.