Unless your hubby has a larger-than-average butt, portapotty height is more likely than seat size to be the issue. If so, the larger 5.5 gal portapotty may be the solution.
It's not his butt that doesn't fit comfortably on the PP. It's his other junk. It hits the toilet seat. That's yukky and I don't blame him for complaining.
I have discovered that not all porta potty seats are the same. Several of the taller, 5.5 gallon PP have seats that have bigger openings and have bowls that are shaped differntly deeper bowls. They are also about an inch bigger in each dimension of the footprint. A couple I've found have the same front to back dimension as a standard round toilet seat.
I think I've found a comfy seat that is as big as a standard round toilet that goes on top of a bucket that has been fitted with a leak proof removable bucket seal (gamma seal).
If it works as expected, I think I've found a good solution for a portable toilet on our boat. I prefer the convenience of throwing wag bags away compared to the hassle of emptying a portapotty or separating toilet.
I've ordered the seat and a few wag bags from
Restop.com . I don't need the bucket or gamma seal. I own a few of them already.
If it meets my expectations, i'll fabricate a base that will provide stability when we pull it out from under the companionway in a lumpy seaway. We'll use something like WAG bags for defecation and solid waste. We will store the closed wag bags inside the sealed bucket until we can dispose of them responsibly.
Commercially available WAG bags aren't very earth friendly, but maybe I can figure out a way to use composting bags with a gelling and anti-stink agent that permits us to dispose of human waste responsibly. We don't use many WAG bags now, so finding an earth-friendly WAG isn't an urgent problem (no pun intended
)
Judy