Posted by Greg Terry on 2nd Mar 2015

It is said that for beginner brewers adding control of fermentation temperatures can be a game changer. When I first read that I didn’t really believe it, and I just fermented my beers in my basement at ambient temperature. The end product was hit or miss, then I had a few batches in a row that didn’t even come close to their final gravity. Some research and some guessing made me think that the problem was that while the air temperature in my basement was fairly constant, the fact that carboys were sitting on a cold concrete floor caused the temperature in the fermentor to drop below what was recommended.

Setting up a fermentation chamber or fridge with a two stage temperature controller would have been nice (and effective) but I didn’t have the room, nor did I want to spend the money. Plus for ales at least my only worry was keeping them warm. I found that submersible aquarium heaters typically have their own temperature controls so you can set them to the temperature you want. They can usually be found online for about $20-$30. Be careful though, some of these heaters either don’t let you set the temperature, or the minimum temperature is higher than what you would typically want for ales.The heater I found was a 75 watt model.

My system is simple. I have a large plastic storage container (which I found around the house). On brew day I fill it with water and install the heater on the inside of it in the water. I usually set the heater to its minimum temperature, which is about 65 °F (I can go higher if the yeast requires it). After I pitch my yeast, I put the carboy in the container full of water, and the heater maintains the fermentation temperature I want until fermentation is done. This works perfect for ale temperatures and since I have started using this I have not had any issues with yeasts not fully attenuating.

So for about $40 you can have temperature control when fermenting your ales that doesn’t take up a lot of space. When you are not fermenting beers you can use the storage container to store brewing equipment.Please note, although the heater manual doesn’t mention it, I installed a GFI outlet for where I plug in the heater, for added protection since the heater is in water.

Picture 1: Empty Fermention Tank

Picture 2: Fermentation Tank in Use