Sometimes the old ways are best. I simply painted rings around my oars at 1 foot intervals. When I reach a spot where I want to know the depth, I simply lower an oar overboard, touch the bottom, and read the water level directly. Of course I estimate the distance between marks. For deeper water I use a long boat hook with similar marks. On a more savory note, I too use the Weber Q grill. It has worked fine for four years. Normally it takes a portable propane bottle but Weber sells a connecting hose to attach it to regular sized propane tanks. Larry Z