Had Washer & Dryer installed yesterday. DW is doing laundry today and I informed her the grey water tank was full and I needed to empty it. She asked me to wait until she was done, I informed her the water from the washer had to go somewhere. She asked "what's the worst that could happen?" As a newbie, I figured the worst case was the Black Tank backing up into the washer. DW decided I had better dump it.</SPAN>