New Installation

[David Draper]

I want to replace my porta-pottie with a simple head and holding tank. I have very little space for the holding tank. What I would like to do is use the space around the head to "mold" in a tank. I was going to use the inner side of the hull for part of the tank along with some pre-existing fiberglass bulkheads. In addition I was going to glass over 3 pieces of marine grade plywood, then glass them in to finish the "sides" of the tank around the head. I would then glass over a plywood lid and bond it on top. My question is this: can I use hull sides and other fiberglass pieces for a holding tank? My concern is that the space is so small, that a custom molded tank would not be large enough.Thoughts...Thanks in AdvanceDavid Drapers/v Carmen's Toy

 

[Peggie Hall/HeadMistress]

I wouldn't do that...

The potential for leaks and other problems is enormous, plus, it would have a major impact on the resale value of your boat. Raritan makes a 5 gallon tank that wraps around a compact size toilet, but I don't recommend it for several reasons, not the least of which is, you wouldn't gain any capacity by replacing your portapotty with it and a marine toilet. When it comes to tank capacity, it's not the number of gallons it holds, it's the number of flushes...and the number of flushes depends on how much flush water is used. Any manual marine toilet will use a LOT more flush water than a portapotty, so you don't gain anything--and most likely will LOSE capacity by replacing a 2-3 gallon portapotty with a marine toilet and 5 gallon tank. If you replace your portapotty with a marine toilet, you'd also have to install a below-waterline thru-hull and seacock for the flush water intake. If you only have a 2-3 gal portable potty now, your best option on a 22' boat is likely to be 5-6 gal portapotty permanently installed and fitted for pumpout. No new thru-hulls, no new plumbing at all except the pumpout hose and deck fitting and a vent line thru-hull. And the capacity in terms of the number of the flushes is equivilant to a 10-12 tank connected to a marine toilet.