De-Icer Sizing & Fish-Safe Winter Care

Fish can live under ice. The danger is a pond that freezes over completely: harmful gases from decaying leaves and fish waste can't escape. Keeping a small opening in the ice all winter is the most important thing you can do.

Step 1: Pick the job

Backyard koi or goldfish pond: you only need a hole in the ice. A floating or sinking pond de-icer, or a small aerator, does that.

Dock, boathouse or lake shoreline: you need open water around the structure to protect it from ice damage. That calls for a larger de-icer or circulator, such as a Kasco or Power House Ice Eater.

Step 2: Size it for your winters and your water

• The colder your winters, the more power you'll need to keep the water open.
• Bigger areas of open water around a dock need a bigger unit, or more than one.
• Check the cord length: measure from the outlet to where the unit will sit, and choose a cord that reaches without an extension cord.
• Plug into a GFCI-protected outdoor outlet.

Not sure? Call 877-201-7383 with your pond size, depth and where you live, and we'll help you choose.

Will a de-icer hurt my fish?

A pond de-icer made for the job only keeps a small area open. It doesn't heat the whole pond. Use a de-icer or aerator built for ponds, plugged into a GFCI outlet, and keep the cord protected.

Fall checklist

• Net or scoop out falling leaves before they sink and rot.
• Slow down feeding as the water gets colder, and switch to a cold-weather food such as wheat germ.
• Add a cold-water bacteria treatment to break down sludge.
• Put your de-icer in before the first hard freeze.
• Never smash the ice. The shock waves stress fish.

Shop winter supplies

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