I have 30 ft of black 3 ft wide gardening material (the kind that lets in rain used to keep weeds out of your bush areas)that I want to stitch into a cover for my small 12 ft pool. as I am about to purchase Pool Rover Junior from aquabot
later next month till then I want to keep it clean anyway. This is NOT black plastic but it is the new black material that absorbs water. Should the cover sit on the water surface or stretch across the top for the most effectiveness?