moldy pontoon deck carpet...please help

[kickstand0929]

I have tried everything I know to try to get rid of the green mold on my pontoon deck carpet. The boat is a 2004 tracker with marine berber carpet and everytime it gets a little wet, it molds. I've tried hydrogen peroxide to kill the mold and pressure washing it all away and the day after I take it out, its back. I've tried changing the location of where I keep it and the same thing. Any ideas please???