Wow one of the coldest nights we have had on Derwent6.. It was minus fifteen on the little weather station we have.. The insides of the windows were frozen and that was with the fire going all night..We didn't want to get out the duvet. We normally get a slight rock from Derwent6 when we move around the boat but not this morning, we were stuck solid... We had been thinking all night what was wrong with the water pump before we went to bed and things were no better when we tried it again in the morning. The gauge was still showing four and it is normally pretty accurate. We had to get some water in it today, so Del walked down to the water tap three times which gave us a hundred litres. When we tried to put it in, the hose connecting the filler to the top of the tank was frozen solid.. This made us think that the water tank could also be frozen. After a few kettles and moving the pipe around we manage to free it off and get water into the tank. The gauge still stayed the same at four so it could be a lump of ice causing the problem. The pump started to work properly again. So it looks like we will be putting water in every day till we start to get a thaw. We then tried to empty our waste tank...no chance!! The pipes were frozen on that as well and the pump couldn't work properly, it might be a fault on the rubber valves on the pump.. We have left some antifreeze down it overnight so watch this space! Knackered from carrying water and clearing pipes we chilled in the afternoon and evening.