Here we cover the basics of pond aeration schedules and explain why and when aeration is necessary for garden ponds. If you have a garden pond that is over 6 feet deep at any point, aeration is necessary. If you are creating a garden pond and do not want to use an aerator, then just be sure to make the pond less than four or five feet deep to be safe.
Why Aeration is Necessary
Aeration is necessary, particularly in ponds six feet or deeper because the water at the bottom of your pond can become depleted of oxygen, for various reasons, such as hot, still weather or insufficient light. When you do not have oxygen in the depths of your pond, the bottom becomes covered with deep sediment that will become anaerobic, or without oxygen. This sediment causes dangerous bacteria to grow that can be harmful to fish and plant life in your pond.
When a pond is well aerated, the oxygen is distributed throughout the entire depth of the pond allowing for fish to breath in the deep water and stopping the growth of dangerous bacteria. Without an aerator, only the water that reaches the surface can be replenished with fresh oxygen.
How to Aerate a Pond
To do a simple aeration your pond, you will need compressed air, a five gallon bucket, air line and an air stone. You attach the airline to the handle of the five gallon bucket and run it to the air stone that needs to rest in the bottom of the bucket. Test it in shallow water to make sure the stone will stay at the bottom of the bucket.
Then lower it into the water to about 6 feet deep and pay attention to the smell of the bubbles that are rising to the surface. If the air bubbles that are coming to the surface do not smell bad, like sulfur, then you may proceed to lower the bucket another foot or so.
Continue lowering the bucket a foot or two at a time and checking the smell of the bubbles. If you hit the bottom of the pond without smelling any sulfur odor, then you are safe, but if you do run into a sulfur smell, you want to be extra careful because aerating the water too fast will kill the fish.
As soon as you find the depth that the sulfur smell is starting from, you will need to leave the bucket at that depth for some time until it is well aerated and only lower it when the bubbles smell fresh again.
The process may take several days depending on the size of the pond. You may lower the bucket another foot when the water is aerated at that depth. Continue this process until you hit the bottom and you will eventually have a well aerated pond that will allow for fish and plants to thrive. Also you may want to check your local retailers for professional aeration systems particularly for larger ponds.
Larger and Older Ponds
If you are working on an aeration system for a newly made pond, then you do not have to worry much about checking the rising bubbles for odor as it takes time for this to occur. But if your pond is old, stagnant and full of algae, then you want to exercise caution. While it is possible and a lot more economical to make your own aeration system, the type offered in this article is only recommended for small garden ponds.
Definitely contact a professional for large ponds that cover more than a couple hundred square feet. This can be a delicate process for larger ponds and consulting a professional is a must. There have been cases of do it yourselfers causing large scale fish kills when attempting to aerate a pond that has been stagnant for a long time.
Also it can be a good idea to aerate a pond that is less than six feet deep if you have substantial fish and/or plant life that may require more oxygen. Your local garden center should be able to advise you on proper aeration for smaller ponds.