Keeping Recirc line from freezing

[Hillcrest Maples]

Using 1/4” tube (1/8” Id) for recirc line on guzzler. I’m concerned the small ID will freeze up hard and not thaw before the sap lines and pump turn on at 32. Should I use 5/16 sap line?

[4 Paws Sugar Shack]

Is your guzzler in a pump box? Do you have a lightbulb in it to kick on at 31 to keep the pump from freezing? I use 5/16 for my recirculation line with a needle valve without issue