I sailed for a week with the ballast valve accidentally (stupidly) left open. I also trailed home with the marine head valve in the evacuate position rather than the "fill with water" position. The holding tank was 80% full. When I got home, there was water in the cabin settee lockers (port and starboard). This water seemed to be dirty lake water. The bilge was full of sewage waste and the toilet bowl was full of waste to the top also. I assume I made two mistakes. I'm thinking the water in the settee lockers came from the failure to close the ballast tank valve and the sewage in the bilge came from doing something wrong with the marine head (besides not getting in pumped out before I left). Any ideas, experience, confirmation of my theories?