Used to remove stain lines on a fiberglass walleye boat caused by stained water. Removes stains easily with some slight rubbing. Very happy with product. Have ordered multiple times.

This product amazed me. It cut through the stain on my boat hull. Simply spray, wait 10-25 seconds and wipe off. Seems dangerous how easily it removed the stain from the hull.

Worked great. Very surprised by the quality. Ordered two more.

This product removed a scum line that was three years old. I let it soak in for around 10 minutes and then sprayed again to wet the area and it wiped off.

I would buy this again!

Tried the BioKleen oxidation remover on my boat with yellowed stains from river tannic acid. BioKleen works better than Attwoods hull cleaner product and at 1/2 the price. The BioKleen people are professional fast and courteous. If you try it once I guarantee you will never go back to the old products you used in the past. For the naysayers... Biokleen didn't pay me a cent to review their product and write this summary.