Should I Turn My Pond Filter Equipment Off in Winter?

 

The short answer? No. In most cases, your pond should continue running throughout winter just as it does during the rest of the year.

As temperatures drop, one of the most common questions pond owners ask is whether they should switch off their pond equipment for winter. It’s a completely understandable concern — you want to protect your equipment, lower running costs, and keep your fish and wildlife safe. However, turning everything off can sometimes do more harm than good.

For a complete guide to cold-weather pond care, take a look at our Winter Pond Care blog, where we cover everything you need to know in more detail.

Can I Turn My Pond Pump Off in Winter?

Your pond pump plays a vital role all year round. Its primary job is to move water through the filtration system, removing debris and maintaining water quality. In winter, this movement becomes even more important.

Water circulation:

• Prevents the pond from stagnating

• Helps maintain oxygen levels

• Reduces the risk of the surface freezing completely

On particularly cold days, the movement created by the pump helps keep a small area of the surface ice-free. This is essential for allowing harmful gases to escape and oxygen to enter the water.

Most quality pond pumps are built to withstand temperatures as low as –20°C, meaning they can safely run throughout winter. The only exception may be very shallow water features (rather than fishponds), where freezing could pose a risk to equipment.

 

Can I Leave My Pond Running Over Winter?

Yes — and you should.

Turning off your pond equipment for extended periods can disrupt the biological balance of the water. Without filtration and circulation, harmful substances such as ammonia and nitrite can quickly build up. Restoring safe water conditions can take time and may put your fish at risk.

If you need to reduce energy usage during winter, prioritise keeping the pump and filter running. These are the most essential components of any pond setup. Secondary equipment, such as additional air pumps or fountains, can be reduced if necessary.

A great energy-saving solution is installing a variable pump. These allow you to adjust the flow rate, sometimes from 100% down to as little as 1%. Lowering the flow reduces energy consumption while still keeping the pond system ticking over safely. This is far better than shutting everything down completely.

 

Should I Shut Down My Pond in Winter?

Completely shutting down your pond is not recommended.

Even though fish are less active in colder temperatures, the pond still requires filtration and oxygenation. Switching everything off can quickly lead to a toxic build-up that the pond cannot naturally break down.

If adjustments need to be made, they should be gradual and carefully considered. For example:

• Reduce the output of a variable pump

• Cut back on additional air pumps if you’re running multiple units

Every pond is unique, and how well it copes with winter temperatures depends on factors such as depth, stocking levels, and equipment setup. If you’re unsure what’s right for your pond this winter, it’s always best to seek professional advice before making any major changes.

If you’re unsure or need further advice, don’t hesitate to get in touch with the team at Complete Koi & Aquatics — we’re always happy to help and answer any questions you may have.

For more information and advice on pond care, check out the rest of our blogs…

Dive Into the World of Koi: The Complete Guide | How to Prepare Your Pond for Spring | Heatwave Survival Guide for Koi Pond Owners