Did you know that if your pond is deeper than 6 ft you many not be getting enough aeration at the lower depth. This can cause problems such as excessive algae growth, nasty smells and excessive pond sludge. Your fish may all be gasping for air at the surface because they do not have sufficient oxygen.
Oxygen is essential at lower depth. It ensures that beneficial bacteria can work effectively to maintain the balance in your pond. Oxygen also enables bottom dwelling animals to thrive. These animals which include snails and worms help keep your pond healthy.
An air pump can remedy this problem by introducing oxygen at these lower depths to ensure that your entire pond is sufficiently aerated.