If you are going to distribute sufficient air to the parts of your pond where air
is essential, Airstones are extremely important.
Every living thing, including bacteria will only survive with a source of air.
Unfortunately, many pond keepers don't realize this, and therefore, they are unaware
of the extreme importance of air in both the pond, and the biological side of the
filtration system. Upon adding Airstones, the benefits of air within the filtration
system will be seen immediately. Because Airstones have a certain life-span, they do
need frequent replacing to maintain optimum performance.