[Brians256]

Methanol works great if you go below 32F. Above 32F, use as pure as possible water for best thermal transfer.

With water, you will need to add anti-corrosion and biocides. Water is a better heat transfer liquid than methanol.

With methanol, you need to watch evaporation. Vinyl tubing is actually quite porous and methanol (slowly) goes right through it. Methanol fumes are poisonous.