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Using VS721 on the side of the hull


Bob asked:

I am about to prep and coat my bottom with VS721. But since the boat sits in its slip until the first of the year, should I or could I use VS721 on the sides of the hull as well. I can see where this will help protect the water line scum from collecting and hopefully have it wash off scum on some long runs. Is this over kill or am I on the right track.



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A lot of boaters use VS721 Bottom Coat above the waterline and it helps reduce the scum along the waterline and makes it much easier to keep clean. The only downside to this is that VS721 Bottom Coat does not contain UV inhibitors and you could get some sun damage in this area. Some boaters apply Premium Boat Shine slightly below the waterline and then after letting it cure for 3 to 4 days, apply the VS721 Bottom Coat over the Premium Boat Shine and above the waterline. This seems to help.

The scum that forms along the waterline, starts off as bacteria. The most primitive life form and the building block for all higher life forms. It is most prolific along the waterline because there you have the perfect conditions of a relatively stationary substrate, your hull, air, water and sunlight. Once you have bacterial slime, which will attach to anything, it will attract algae, which feeds on it and eventually higher life forms like
barnacles, zebra mussels, etc.

The key to keeping your boat pristine is keeping the slime at bay. You can do this by periodically wiping the water line with a sponge, rag or brush. Regular use of the boat will also eliminate the attachment because of the abrasion of the water against the hull.

VS721 Bottom Coat will seal the pores in your gelcoat and reduce the surface tension on your hull which will make the slime easier to remove and make it more difficult for the slime to attach in the first place, but as I said, bacteria will attach to anything if the conditions are right.


Thanks for your question,

Captain Aurora

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