Bob wrote:

You raised a question I have been think about lately. When people say
for "below the water line" applications, just what does that mean?

If the thru-hull is below waterline at least 50% of the time--especially
while the boat is at rest (wave, wake, tide), it would be wise to
consider it to be a below-waterline thru-hull. If it's only submerged
when the boat is heeled--which would also imply "only when you're
aboard," it's not.

That said, I would not connect ANY clear hose to any thru-hull. 'Cuz
IMO, whether it's hoses or anything else, you can never regret erring on
the side of caution. And fwiw, I've NEVER seen any clear bilge discharge
hose. Boat builders are very cost conscious...if there weren't a good
reason to stick with marine-grade bilge pump hose, they'd use something
else that's cheaper. And also fwiw, I wouldn't use corrugated hose for
anything on a boat, anywhere.

But that's what I'd do. It's your boat...your choice.


--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://shop.sailboatowners.com/books...ku=90&cat=1304