I have read all the "stickies", but not sure if my question was answered. I have a 97 355 Aft Cabin Carver. It has two vacumflush heads that use freshwater for flushing. The systems are Jabsco quite flush/electric marine flush with push button flush controls. After flushing the forward head, water will remain in the bowl. However, in the aft head the water is gone after a couple of minutes, but the vacumflush does not run as some people have stated. Both hoses exit the head horizontally and downward on the way to the holding tanks four feet away. What is causing the aft head to loose water, and what is the fix? One last question, is the Jabsco unit located at the base of the head a macerator or a pump? It sounds like it is macerating, you know what! Thanks for all the help.