Electrolysis VS Rust-oleum Rust Dissolver Gel rusty fuel tank on Skid loader

My skid steer had a rusty diesel fuel tank. Tried the electrolysis "cheaper" way to do it, but the phosphoric acid in the gel worked faster and better at only $12. Pressure washer, hot water, and the gel or a lot of phosphoric acid would have made this job go a lot faster. Now I know. Cleaning this tank that is built on heavy equipment is a lot harder than a removable tank, limits the options.