Do you Need to Run your Pond Pump in the Winter

frozen garden pondShould I turn my pond pump off for winter? this is a question that gets asked a lot as the winter draws nearer.

Leaving your pond pump running over winter depends on the type of pond you have and the climate you live in.

If you live in a region that only freezes on rare occasions you can run your pump through the winter without any problems.

If you live somewhere that freezes on a regular basis or for prolonged periods of time you may want to turn off your pump to prevent damage to your equipment, although we would recommend running your pump for as long as possible.

If your pond is full of fish you are better off leaving your pump on all year including the winter, but if your pond is an ornamental feature without any livestock there is no need to run your pump in the winter unless you like the sound of running water from features like waterfalls.


Why you should leave your pump running during winter months.

If you leave your pond running 24/7 even in the winter your pond will thrive, the constant flow of water not only keeps the water clear but circulates the oxygen rich water from the ponds surface, it also stops your pond going stagnant. 

Debris that is suspended in the water will be filtered out of the pond and the bacteria in your ponds filter system will stay alive during the winter months ready to spring into action when the weather warms up.

If you have fish in your pond its essential to stop your pond freezing over, if the surface of your pond freezes over it acts like an ice cap trapping harmful toxic gasses underneath the ice which will affect the health of your fish and could even kill them.

Keeping the water in your pond circulating will help stop your pond freezing over when winter hits, the constantly moving water is less likely to freeze than still water.

In winter, you should turn the flow of the water on your pump down by about 50%, this is to stop too much flow while your fish are in a state of hibernation.

If you have a waterfall you can leave this running as the water falling of the edge into your pond will help keep an area of your pond open even if the rest of the pond has frozen over.

If you notice that ice is forming on your waterfall causing a dam effect you should turn off the flow of water to the waterfall, because if it does dam up the flowing water will overflow over the sides of your waterfall and not back into your pond, if this happens with the pump running your pond will empty so keep an eye on it.

If you do decide to run your pump in winter you should raise it up from the bottom of your pond if it’s a submersible pump, this will minimize the mixing of the different water temperatures from the bottom and surface of your pond as this could affect your fish, about 30cm (12″) is advisable.

If you have an in-ground pump you should be Ok for the winter as the surrounding soil should insulate it.

If you have an above ground pump you should insulate it if you want to run it through the winter, if not you should turn it off to protect it.

If you have a very shallow pond with a submersible pump it would be advisable to turn the pump off and remove it from the pond, a shallow pond has more chance of freezing solid which could damage your pump, if you have fish you will probably have a deeper pond, this really only applies to ornamental ponds.


When you don’t need to run a pump in winter.

If you don’t have fish in your pond there is no reason why you would need to keep your pump on during the winter months, so you can turn it off, if it freezes over there is no livestock in your pond to harm.

Another benefit of not running a pump during the winter is the cost of electricity that you don’t have to pay for unless you have a solar powered pump.

If you decide to turn of your pump for winter but you have fish in your pond you will need to take other measures to stop your pond freezing over such as a pond de-icer or an aerator.