The quick answer is “Probably, no”. If your pond is less than 4 feet deep, it typically will not need aeration during the summer months, at least here in Minnesota. The waterfall and aquatic plants will add enough oxygen to keep healthy levels of oxygen in your pond water.

Why is oxygen needed in my pond?

Oxygen helps keep your pond clean! The beneficial bacteria in your pond water need oxygen to live as do your pond fish and pond plants. When the bacteria are doing their job well, the system balances giving you a pond that is easy to maintain and enjoy!

If your pond smells like an old swamp, then you probably need an aerator. The smell comes from anaerobic bacteria decomposing plant material (i.e. muck). Anaerobic bacteria live and thrive in places with little oxygen. That stinky smell is a notification from your pond telling you to aerate and/or clean your pond! The picture below shows how an aeration system is placed in your pond. The aeration stones lay on the pond’s bottom and bubble fresh oxygen into it.

Will I need aeration in my pond during winter?

Aeration in winter looks different than summer aeration. The key is to leave a hole in the ice. (If you don’t live in a cold climate like Minneapolis, MN, then ignore these directions!) The hole allows air exchange (called de-gassing) between pond water and the atmosphere.

If you plan to keep fish in your pond during winter, then “Yes!” you will need aeration!  The ice seals the pond off from fresh oxygen. Typically the waterfalls are also turned off and all the water lilies and pond plants are dormant.  Pond fish will be in a slow dormancy state but will still need plenty of oxygen if they are to survive.

Attaching a return de-icer to your pump is an easy way to aerate your pond in winter. This is basically a pipe attachment that spits the pond water straight into the pond instead of running it around to the bio falls or waterfall.  The pounding water keeps a hole open unless the temps fall below -10F.
We have successfully kept koi fish in our pond several winters in a row by using the return de-icer method.

You can also use an aeration stone and a floating pond heater to move the water and leave an opening in the ice. They also need to be checked, especially when temps fall below 0F.

For more information about aeration systems, visit: https://www.aquascapeinc.com/pond-aerators
You may also want to contact our technicians about your pond. They want you to enjoy your pond, clean, clear, and balanced!