I use a seedling mat for heat but I have it hooked up to an inkbird, inside a mini-fridge. Inside the fridge, it's enough heat for 5 gallon batches too.Anyone use seedling mats for heat? I bought a 3 x 20 to test it out and it seems it’ll do the job on a gallon glass jug. Downside is that I don’t have a temp controller yet but I think I might struggle to find a spot for the sensor. It comes about 2-3 inches shy of wrapping around