dedicated fresh water toilet tank

[jeffatoms2]

In the "Fair Winds" category, a quick, unofficial survey of boat owners across the spectrum indicates that the number one item that people dislike about boating is stinky marine head and related holding tank smells.  It can be a real compromise and a deal breaker for some to avoid using their boats.

In summary, it is due to four things: first, decaying marine life due to the use of a saltwater flush, second, old warn out permeating waste hoses, lack of odor eliminators and finally the location of the exhaust breather which for some stinky reason Bavaria put just port of the cockpit combing of our cockpit.

We have mitigated the off gassing caused by the use of salt water flushing by opting to use fresh water; specifically we have seven one gallon water jugs in the corresponding shower stall which give the added benefit of indicating how full the holding tank is.

The problem is the seven jugs, full or empty, are awkward and messy and just a hassle that are in the way.  I would like to add a dedicated 7 gallon fresh water tank under the sealed floor of the head with a deck fill just aft of the existing deck level wast pump out.

So far, I have acquired a 35 liter flexible water tank from HiNelson in Italy and a new deck fixture.  I've looked into the space with my boroscope and it looks doable. 

Curious has anyone else freed up that space on the floor in front of the sink and toilet or even better, added a dedicated fresh water tank for this purpose.

If so, what can you say before I proceed by cutting a flush hatch into the floor?  SCARY!

Hoping for some experiential feedback.  Right now it looks like my access port/hatch will be along the raised stringer/chase separating the shower basin from the head floor.

Still struggling adding photos which I have and will do when I figure it out.

[Yngmar]

Our friends Nautitech 46 was freshwater flushing from the factory, because it's a pretty wastefully set up boat, watermaker, generator to power it, big fuel and water tanks to feed all that, predictably resulting in weight problems (catamarans are more sensitive to those than monos).

Their toilet (3) smelled the same as ours, which was not much at all. Better spend the money on odor-proof hoses, making sure the holding tank doesn't leak a drop and old spills are completely cleaned up and disinfected, including whatever has run down into the bilge and the hollow stringers in ancient times. Then there's nowhere to smell from except during business hours 

[jeffatoms2]

All great comments, thank you.  Regarding the monitoring of the holding tank capacity, do you or others have any fail-proof guidance to knowing when the tank is full?  We had one overfill in the past and it trickled down into the dish cupboard above the sink.   Truly disgusting and avowed, never again! 

Again, a design failure for many reasons in placement of the breather vent if you ask me.