If you find that the water in the heads smells after a short time it may be that the water being pumped in is polluted.
This is often the case if the boat is in enclosed waters such as a locked marina (obviously you will be using a holding tank in this case!).
A solution is to flush the heads with fresh water from the shower.
This can also reduce the sulphur smell of the heads when the boat has been left for a period of time. It is generated by bacteria in the sea water in the pipes, flushing the system through with fresh water before leaving the boat may reduce the smell when the heads is first pumped.
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