I think perhaps GG didn't realize there would be a hole in the ice layer,
but I'm assuming, so hope I'm not committing the Ass U Me injury from doing
so. ;o) ~ jan

On Mon, 02 Feb 2004 , GrannyGrump wrote:

Someone posted a message about raising the water level before the freeze
and melting a hole in the ice and pumping a couple inches of water out
from under the ice. The sheet of ice above the water insulates the
water underneath and saves on the electric bill as well as keeping the
fish alive.

This would accomplish the gaseous exchange, until there was no more
oxygen in the air between the water and the ice....

Didn't know that was a problem, since the hole is still open and can't
refreeze with the water not reaching it. Are you telling me hydrogen
sulfide is heavier than air and will be trapped in the space displacing
oxygen? Hal

~ jan