Anne Lurie wrote:

Mike S., you may be the guy to back this up -- as I recall, propane gas is
*heavier* than air, so any leakage would not disperse into the air, but
would instead hang at ground level waiting for the next ignition source?


A repost from friday also explains this effect also.

Having the gas bubble up from under the water will not work. You must
maintain a constant stream of gas.
The volume of gas can vary, but the supply cannot be broken.

Repost:
The only way the bubble method MAY work is if you have a standing pilot.
To help maintain the flame.
Even then you will probably have a very unstable flame.
(ex. fireball... steady pilot flame... fireball...steady pilot
flame...Fireball...fireball... fireball...steady flame...etc, etc, etc...
You get the picture...


Mike S.
Chagoi
http://ourkoipond.com