CLR will take it right off. I used leverage on my boat and the scum line from sitting in the muddy Maumee for a day hardly shows up

How do you guys get all the hull surface? Do you guys use a hull cleaner when its in the water for the part of the hull the trailer bunks cover up?

I use on-off, but I feel like it eats up the gel-coat. Leverage does a great job in preventing the hull stain.

Good thread.

I have not found any product to put on the hull that will stay on the hull once the boat is in the water for the day.

I do not have a staining problem were I now boat but I did have some when I kept my boat in Tarpon Springs and had to go up the Anclote River.

One of our buddies we boated with for years was a chemical engineer and he laughed at me for years griping that even after waxing the boat, it would yellow up. He finally enlightened me that it typically is not from lack of wax, rather it is the chemicals in the water reacting to the wax. Therefore, almost impossible to prevent the yellowing. We always use the liquid toilet bowl cleaner on a small rag and just rub it lightly on the yellowing areas, let it sit for a few minutes so the chemicals can break down the yellow buildup, then wipe it with a rag with the cleaner a second time and rinse with the hose. The bad part is most of these solutions to remove the staining also removes the wax so occasionally you may want to reapply the wax throughout the summer where the yellowing takes place the worst. Good luck. BTW, our worst experience with the yellowing of the hull was extended stays in Lake Michigan where the steel mills have heavy chemical concentrations. Just because you can see the bottom and it appears very clear and clean, there are still chemicals!!!!

If Sunkin would quit p*ssin' on Reggie and the Fountains all the time, we wouldn't be having this problem...:D :D :D

Try Kaboom Shower Cleaner. Lowes is a major supplier.

It is a weak solution of phosphoric aciid.

star-brite hull cleaner, 8.00 from Walmart, spray it on and hose it off. on-off seemed way to harsh and I don't use it anymore, still have 3/4 of a gallon of it.. Wet sanding is just BAD advice.

Tom - As was probably stated, I did not read the whole thread. That boats water line was cleaned once a weak with muratic acid while I owned it. That yeallow will run off like rootbeer. Just don't where nice clothes when you do it, You can reduce it down to like 60 acid, 40 water. MR

I used to use On Off but it is basically muriatic acid as far as I could tell. It will take your fingerprints off :hitfan:

Now I use FSR. it is a blue gel that is easier to apply than On Off, you put it on, wait a little while and it turns white... then just rinse.

My boat is in for paint now and I'm having the bottom sprayed as well. My brother's boat is like that and there is no more yellowing issue... Awlgrip is less porous than Gel coat