Most of the products discussed here to stop rust are acid based and convert rust to iron oxide. Most farm supply stores such as Tractor Supply sell products to treat rust, one of the names that it is sold under is Ospho, I also believe it is much less expensive. Autozone also sells a similar product as do most auto parts stores. Rustoleum sells spray cans that are called Rust Reformer that works quite well on lightly( surface rust) rusted surfaces, it is kind of a primer/rust converter. Usually it is best to let the product dry and cure for 24 hours then follow up with a coating of paint. As stressed in other posts, don't get it on your skin, use eye protection, and have the area well ventilated. I have used these products on my RV's and classic cars and they work well if you follow the directions, money and time well spent.