"Joel" wrote in message
4...
I recovered the liner with snow, my question is this

its pretty much an airtight lid over the pond, the bubbles are keeping the
surface of the water moving so the gases dont settles over the water, but
what about the airpocket I have created with the cover, is the gas
collecting in there, should I have some venting happening ? could I just
over the liner once in a while to put fresh air in there ?

If you know that the air pump is pumping air to the bubbler inside
the cover then there is fresh air comnig in through the bubbler. If
the cover doesn't look like it will explode, then the air is venting
out somewhere. (You don't have anything near an airtight seal.)

Jerry