Last week I transferred 5 gallons of a maibock to a Better Bottle to lager. I've rigged a 48 quart Coleman cooler to be a swamp cooler. It is currently in an unheated guest room at my house. I had no problem fermenting in the high-40's/low-50's in this rig, so I figured if I put a few 2 liter bottles filled with ice in there, I could get it down to the mid-high 30's and it would be good for lagering. It has now been 5 days, and I can't get it to go any lower than 43 degrees. I can maybe fit 1-2 more bottles in the swamp cooler, but I'm not sure what good that's going to do.
I want to know if it would be fine to lager my maibock at this temperature, so long as I give it a couple weeks longer than planned. I have a mini-fridge, but it can only fit a 3 gallon carboy, so my only other option is to bottle 2 gallons of it, bottle lager that, and lager the remaining three gallons in the mini-fridge. But I'd prefer the option that requires less effort and more patience, if possible.