I normally get by with a 1 stage controller as it's always hot in Florida and I rarely struggle to keep temps above 60 degrees, but it's supposed to remain in freezing temps for several days and I have a batch of an oatmeal stout with Nottingham yeast that I just put in the fermentation chamber last night. I'm going to struggle to keep it in the right range. I have a Johnson A419 controller (I think that's the model) but it only has 1 stage temperature control. The problem is that it might jump into warm enough ranges in my garage during the day to mess up stable fermentation. So I'm thinking about putting a lightbulb/can heater in the ferm chamber and just running it 24/7 and keeping the temp controller on the fridge so it can still cool when it needs to. I bought a 40 watt bulb that I'm hoping will be enough but not too much to run constantly. Is this a stupid plan? I can't imagine the 40 watt bulb would be able to overpower the cooling capacity of my refrigerator. What do you guys think? Ambient temps in my garage will probably drop into the mid or high 40s at times.