Try not to let the bilge pump dispose of your oily bilge water for you. The oil slick you leave behind not only looks bad, it also harms the environment and is a criminal offence. Use absorbent bilge pads, available at most marine stores, to line your hull. These pads will absorb the oil, but not the water. Soaps and bilge cleaners do nothing to mitigate the harmful effects of oil or gas in the water. Instead, they spread the hazardous waste out over a larger area, thereby affecting even more of the shoreline.