I have a 600 sf golden garapa deck that's about 18 years old. The gaps between the boards gets choked up with debris and then the boards cup up. They used to be about 1/8" wide. In many places water can't get through the gaps any longer. I'm thinking that I need to widen the gap between the boards so the debris can freely fall through the gaps. To do that I was thinking of getting a track saw to help me keep the lines straight. How wide should I make the gap? 3/16" or 1/4"? Being garapa, what should I treat the edge of the boards along those gaps? Need blade recommendations so I can get a consistent gap width without wandering. Should I use a router to round off the cuts? Can I even get a router to fit in the gap? Note that there's a rubber membrane under the deck, between the deck boards and joists. It forms a channel between the joists that drains the water to one end and discharges to a roof gutter system. Needless to say, I don't want to destroy or nich the rubber membrane. It keeps the patio below nice snd dry. Also, I'm looking for a sealer for the deck boards that does not contain any coloring. Do they make anything like that any more? I initially could get a clear sealer but since then I could only find a yellowish transparent sealer, that wears unevenly. Any recommendations would be appreciated.