Eliminate Black Water Tank Odor | Green Kap Envirovent Discover the easy way to eliminate the black water tank odor from your motorhome or RV. The Green Kap Enviro-Vent from Green Shift Technologies will get rid of the motorhome bathroom smell and you will never have to use chemical again. Works with house-boats too. Greenkap.com~Site InfoWhoisTrace RouteRBL Check