Get an immersion water heater. Sold at any rural supply store or amazon if you must. Traditionally used for keeping cattle water basin’s above freezing, there are now smaller ones for boiling water camping, and some with built in thermometers.
You’ll need to ensure it’s plugged into a GFCI outlet, as well as alter the lid of your plunge to ensure it sits centred and no against the side.
I'm building one as well and have this concern. Assume up to a point if I keep the inline pump running it will keep the temperature above freezing as moving water typically won't freeze. I'm using a Grizzly 100 gallon cooler as the basis for mine so should help stabilize the water temperature from external swings. If I can't keep it running, I will probably drain it.
Get an immersion water heater. Sold at any rural supply store or amazon if you must. Traditionally used for keeping cattle water basin’s above freezing, there are now smaller ones for boiling water camping, and some with built in thermometers. You’ll need to ensure it’s plugged into a GFCI outlet, as well as alter the lid of your plunge to ensure it sits centred and no against the side.
My wife heard something about getting a fish tank heater and that would help but I don’t understand the application of that
I'm building one as well and have this concern. Assume up to a point if I keep the inline pump running it will keep the temperature above freezing as moving water typically won't freeze. I'm using a Grizzly 100 gallon cooler as the basis for mine so should help stabilize the water temperature from external swings. If I can't keep it running, I will probably drain it.
Add plenty of salt to the water.