PO. let my boat in Lake Erie with no bottom paint for a year without using it do to an illness.When I got the boat the marina that took care of the boat had scraped off most of the snails but never cleaned off the stain left behind. After sitting all winter nothing I tried worked to remove the dried stain. So I sprayed it with easy off oven cleaner (caustic base or lye) and instantly it started to soften the stain. Two years latter I finely cleaned the rest of the hull that required me to suit up and lay on my back and clean what was left . Step 1. apply easy off let sit Step 2. lightly scrub with brush Step 3. sprayed down with in my case a cheap electric pressure washer.
