Keeping your fish alive through winter may sound like a daunting task, but it's actually very simple! Fish aren't eating, so don't feed them. But they're still breathing, so make sure there's a opening in the ice in your pond for them to breathe.
You can keep a hole open in the ice in your pond with an aerator or a de-icer or both. Not sure which one is best? We've spelled out the benefits and drawbacks of using aerators and de-icers in winter so you can make an educated decision.
Floating Pond Thermometer
Floating Pond De-Icer