Frances Whited wrote:

When you use an airstone, you need an air pump too, right? Where do you
locate the air pump so it is protected from the elements?

Since my pond is fairly small, I place a 2x4 across the pond (above the
water), and place the pump along it. I use a piece of pvc pipe, which
is attached to the board, at a 90 angle, so that it goes down into the
pond. I attach the pump to the upright, and place an upside down 5 gal
plastic bucket upside down over it for cover.

THE key, is to make sure that the air line runs straight down, as any
dips or sags will collect water, which will freeze.