A few pond owners have contacted me recently with some very good questions on how to aerate a larger pond that’s pretty shallow. Should they do it in the winter and if so, how?
To be more specific, we’re talking about ponds in the 1/8 to 1/2 an acre in surface area and something in the range of 3 to 6 feet deep. In ponds like this, a traditional aeration package probably would help but it’s not really well suited to the depth of the pond. For a pond with some depth to it, I usually suggest moving a single diffuser from the deepest part of the pond in the summer, to a more shallow location in the winter months. This article on winter pond aeration explains it in more detail.
But in shallow waters during most of the year, you normally will need more diffusers to cover the same size of pond, as you would a single diffuser in a pond that’s 10 to 15 feet deep or greater. In other words, the deeper the pond, the less diffusers you’ll need. So shallow pond aeration kits were developed to work specifically in large ponds with shallow conditions. They use a single compressor coupled to multiple diffusers spread throughout the pond. The compressors are usually a bit less powerful and this needs to be kept in mind when using them in colder weather.
During the summer months, it’s a good idea to run all of the diffusers and spread the air evenly throughout the entire pond. This way you get a very consistent and stable degree of oxygenation all over the pond area.
Things change a little bit in the winter however.
Remember, the idea is to use an aerator to keep a spot open in the ice to allow any build up of gases in the pond to be released, and fresh air to come in and help with some oxygenation. The release of bad gases is probably more important and the hole doesn’t have to be very large to do this but ideally you don’t want things to freeze over in the coldest of weather.
So when you use a shallow pond aerator to do this work, you want to continue to use all of the diffusers and relocate them in a much tighter array than you would in the summer. Put them in a concentrated spread of maybe a few feet apart to concentrate the bubbled air. This adaption will provide the best chance of keeping the surface ice free in that part of the pond even when temperatures get well below freezing.
To get a better idea of what makes up a typical shallow pond aeration kit, take a moment and watch the video below.