I have done a lot of searching on the forum. I have untreated canvas to use and though I store my boats well, I would like to protect my canvas better so I can be a little less careful. I already put copper naphthenate in my filler. I'm trying to figure out some option still available in 2020 for treating the inside of the canvas: -Copper naphthenate: Still available in the US, turns wood green. Would not impact the filler is my assumption if painted on the inside of canvas and dried. If I treat my canvas with this would it turn my feet green if my boat gets wet? -MX3 mildewcide (Carbamic acid, butyl-, 3-iodo-2-propynyl ester) or ADD-2(2-(4-Thiazolyl)Benzimidazole ): It mixes with oil or water base paint, I was thinking mix it with thinner and paint it on the inside of the canvas. Would this last? Would it poison me if my boat gets wet? I assume something like this is applied to the mildew treated canvas available from boat suppliers; perhaps when this is made at the factory they have some other carrying agent that keeps the chemical where it should stay? -Experimental idea: Thin down pine tar, apply to inside of canvas, apply a non-organic dust like diatomaceous earth (DE) or something like that to keep the pine tar from being sticky. Pine tar is a natural anti microbial, correct? Easily available, but would I have spontaneous combustion issues? filler sticking issues? smell too bad? -Other ideas?