>I've used toon brite on my pontoons and it works great. But I
>thought it smelled familiar. I opened a gallon of muritic acid
>and it smelled the same. I tried it with the same results.
>Spray it on and wash it off. At a quarter the price.


Muriatic acid is an impure technical grade of Hydrochloric Acid; that's why it cleans so well. Be sure to cover your hands with vinyl or rubber gloves and wear eye protection. Just plain old white vinegar will do the same(much cheaper too), but will not work nearly as fast. My Dad and I cleaned the aluminum hull of a 40 ft. houseboat years ago with gallons of vinegar and Muriatic for the really tough spots before we applied antifouling paint.