If you need some type of sealent they sell them at most marine centers. My 14' aluminum boat was getting pin sized holes for the last two years. So we baught a couple cans of this paint on clear coating, a few coats on the inside and one on the out side, and they stopped. You should be able to get stuff to get rid of the built-up too. Hope this helps.
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They say that the man that gets a Ph.D. is the smart one. But I think that the man that learns how to get paid to fish is the smarter one.