Home Distiller

Have a thought for cold temps that are coming...if I used a 2 inch copper pipe, capped one end, insert in mash, fill said tube w hot water and insert an aquarium heater Inside the tube. I wonder if it would keep a mash warm enough??? The idea of adding plastics and rubber from the heater directly to the mash alcohol ,to me isn't a good idea

you will run into stratification. I would recommend a foam box with a light bulb and muffin fan.

run the bulb with a thermostat. control the temp outside the mash, inside the box.

The aquarium heater will work. I think your going to need a blanket around the fermenter though. I use a submerged heater and an insulated box with a thermostatically controlled fan to regulate the temp inside the box. The ferment will give off a lot of heat on its own. The aquarium heater will supplement when needed and the fan will keep things at the optimum temp when the ferment is going hot and heavy. YMMV

The main reason for needing to heat is heat loss. With plenty of insulation you hardly need any heating at all. Aquarium heaters are probably the worst and I've only ever tried to use them twice. Both times they left the bottom of the fermenter cold, so I only use them to get the wash up to temperature. For my large fermenters that don't fit in an old fridge, I wrap them in old duvets, blankets and mylar. All are heated from underneath with 40W to 100W depending on the seasons and controlled with a thermocouple in the wash. In summer I often have to leave some insulation open and have a fan connected to the same controller to cool it if necessary.