I was looking. The Instant hull cleaner and on/off products I used have that oxalic acid in it. And they did not work. Is there a specific product you were thinking of? I assume it is more concentrated
Hello. I have an ebbtide boat. Fiberglass gel coat. I have the tan/orangish layer on the bottom of the boat. I tried everything I know of on it. Instant haul cleaned and on/off. I can scratch it off with my fingernail. Takes effort though. A boat shop said to use a razor blade...