On Thu, 29 Jan 2009 16:24:55 -0800, John Navas
wrote:

On Wed, 28 Jan 2009 18:27:21 +0700, BruceinBangkok
wrote in
:

On Tue, 27 Jan 2009 19:28:28 -0800 (PST), Peter
wrote:

Run a clear plastic hose (the one with the string embedded in the
tubing wall) from the drain of the tank to the water tank vent. You
then have a site guage for the tank. If you are a sailboat you may
have to run the line across the boat so when it heels you don't drain
the tank.

You don't even need then vent connection, just run the tubing a couple
of feet higher then the tank so it won't run over when the boat heels.

Surge siphoning can still be a problem. I speak from painful
experience.

I can understand surge but siphoning when the outlet is above the
inlet?
Cheers,

Bruce