On Sat, 18 Dec 2004 17:14:53 -0500, Mike Patterson
wrote:

Since you work with mercaptin, I'd like to pick your brain a bit if
you don't mind.

I have this small project I'd like to try where I'd bubble propane
from a 20lb tank or natural gas from the house line from the bottom of
my goldfish pond so that it burns at the surface. Kind of a floating
flame effect.

One thing that concerns me is that the mercaptin might build up in the
water to toxic levels, either from the gas contacting the water
directly via the bubbles or else from the film of soot that forms on
the water surface (I've done some experimenting in a #10 tub already).

Would you know anything about this, or know where I could find out? I
looked up the MSDS on it, but I couldn't find out anything about
concentrations in water affecting fish.

Any comments or suggestions?

Call Disneyland. Seriously.

They bubble Natural Gas (with mercaptan as delivered) through the
water in the river (from pipes on the bottom) and light it on the
surface for the Fantasmic show twice a night.

And AFAIK the fish that are in the river (to eat the mosquito
larvae) are doing just fine, and it doesn't bother the Ducks, Coots,
Herons or Egrets either. Well, except for potentially barbecuing the
few new birds that do not know /not/ to be there when the show is
running yet...

They use a spark-lighter to ignite a 'pilot jet' from the bank out
over the water to the end of the gas-bubbler pipe. It takes quite a
bit of flame on the water to stay lit on it's own so they can turn off
the pilot light. And of course, there's somebody there watching while
the effect is running, with an E-stop button if things go wrong.

You would only want to use Natural Gas for this, it's lighter than
air so if the fire goes out it won't build up as easily. Propane can
easily make a puddle of unburned gas that stays over the water surface
and builds up, and when it finds an ignition source it can suddenly
get VERY exciting.

-- Bruce --
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
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