I've washed my film for at least 15 years using the fill and dump method. I prepare the amount of water needed at 20 degrees c, fill the tank and invert it 5 times a dump the water. This is followed by filling the tank and inverting 10 times, 20 times, 10 times and finally 5 times each with fresh water. I've never had a film deteriorate in since I started using this method. The whole process, from preparing the water to hanging the film in the drier takes less than 20 minutes.