an air stone should only be about 12" down, and it is important to keep the water
moving to provide oxygenation to the fish who are sitting on the bottom, especially
if there is any rotting organics down there. hell with the warmer water, make sure
oxygen is getting to the bottom and the warm deoxygenated is moving to the top.
Ingrid

On Thu, 3 Jan 2008 18:23:01 CST, Michael Lee wrote:
The concern is moving the warmer, deeper
water to the colder surface can cause problems also.

actually, water does not really stratify much in a pond. it is essential to
oxygenate the water and keep some up and down movement going. a single 100 watt tank
heater below the air stone(s) will keep the air hole open.

when (not if) the ice freezes over use a 1.5 inch spade bit in a cordless drill and
drill holes liberally, then drop the airstone back in.

Ingrid

On Sat, 5 Jan 2008 20:24:33 CST, "Peter Corser" wrote:
Don't, under any circumstances use an air pump/air stone to bring water to
the surface - this will do far more harm than good in allowing the overall
pond water temperature to fall to too low a level (still water will have 4
deg C minimum - a characteristic of water which is why ice floats).

If you do not have a waterfall attempt to ensure that there is heating it with a region or a hairdryer placed on the ice, forming a warm Pan ice cave hole. This will allow harmful gases to escape. Whatever happens, do not stop this action by the formation of the shock waves can kill fish, ice. Can also be used near water power realize how dangerous this may be.