Why Are There Bubbles in My Pond?

Bubbles in your pond can be due to a few different causes.

Decaying Organic Material

Decaying debris from plants can be a source of bubbles in your pond.Decaying debris from plants can be a source of bubbles in your pond.
Noticing bubbles in your pond may mean your liner or pump requires maintenance, or it could indicate a clogged filter. By eliminating a few possible causes of the bubbles, you can get a better grasp on what may be the cause and begin taking steps to eliminate the source.

If your filter or skimmer is clogged or has stopped working, you may be noticing bubbles because of an accumulation of plant matter decaying on the floor of the pond. Use a pond vacuum to remove as much debris as you can, and see if the bubbles cease. If they do, you will need to add an additional filter or skimmer to prevent future buildup and a decrease in water quality.

Fish

If you have fish in your pond, especially larger fish such as koi, you may be noticing bubbles from them. Often times while feeding, koi will expel air from their mouths and create bubbles. As long as your fish are not at the surface gulping air, there is nothing to be concerned about.

Liner Puncture

If your liner or prefabricated form has a hole, you may be noticing a steady stream of bubbles rising from the location of the puncture or crack. These holes will be uniformly spaced and continually emerge in the same part of your pond. Monitor your pond for water loss to confirm a leak. Drain and seal the leak and refill the pond.

Insect Larvae

If the bubbles appear to be floating on the surface of your pond and not rising from the bottom of the pond, you may be seeing insect larvae. Some insects form air pockets around their bodies while they are on the surface of the water to breathe and aid in floating. Look closely at the bubbles and see if there is a small worm-like mosquito larva or dragonfly in the center. If you find the insects problematic, add fish to your pond to control populations.

About the Author

Andrew Leahey has been a writer since 1999, covering topics as varied as technology how-to guides and the politics of genetically modified organisms to African food supplies. He is pursuing his J.D. while renovating an 1887 farmhouse located in the New Jersey Pine Barrens.