The water tank should be at least 3 times. It's almost impossible to clean the back of the lower teeth. Previously I had a dental jet Braun Oral B that ended up being out of order, and dental jet Viveau is one who cleans it best: it connects directly to the water tap is opened more or less varying the pressure according to his taste. Its defect is that in general we should tinker a bit so it does not leak.
