Why are pond
water heaters so important for ponds that freeze during the winter?
They create a hole in the ice, large enough for toxic gases to escape.
No, the purpose of pond water heaters is not to keep the fish warm.
In fact, for the sake of the fish, you do not want to heat the entire
pond. You truly only need a hold for the toxins to escape.
If you do not have the money for a pond water heater, you can still
create the all-important hole. Do not, however, pound on the ice,
break it, or create noise. Rather, heat up a pot of boiling water,
take it outside and set it on the ice until a hole melts. Be sure
to hold on to the handle – the fish are not going to want a
pot in their pond!
Also, realize that you generally only need a pond water heater for
larger ponds. Small ponds need only a de-icer.