Heating a 200 litre fermenter

[Salter]

Last winter I used a fish tank heater turned up to full and wrapped a sleeping bag around my 200l drum. Works pretty good

Awesome! I was just looking at my fish tank thinking... "what's stopping me from using one?!"

Fish tank heaters work great, just be careful of the cheap ones. They don't have a high enough density and end up floating in a wash. This could cause them to fail (cracking open, leaching nasties into the wash) and potentially lose your wash. Or even start a fire.

I've got a good quality one, and a cheap one. To the cheap one I fastened a small stainless steel hose clamp to the bottom of it (lose enough not to break it) and now it sinks nicely in a wash. Hose clamp and cheap heater cost less than a more expensive heater.

Do you need some kind of way to stir the product?

A wash has enough Brownian motion to keep the yeast moving around and doesn't need stirring. Yeast produces carbon dioxide gas which causes it to become less dense and they float to the top, helping to stir the wash. They sink again when the carbon dioxide is released and the process repeats. When there is no sugar left they sink and the wash clears. They also make alcohol. Gotta love 'em :romance-kisscheek:

Thank you for the advice db1979

What if the temperature drops rapidly (winter nights) or the product (wash) is towards the end of its fermentation process? I'm guessing insulation should be used, is that right?

[db1979]

Yep, insulate the fermenter. You'd know from trying to boil water on a stove that water takes lots of heat to change temperature, just the same it holds heat for a long time too. So combination of heater and insulation is all you need.

[stillts]

anyone using the "SunSun" brand aquarium heaters off Ebay?

[siiren]

I picked up a few IBC heaters cheap off marketplace. Work a treat with an STC - 1000 and a few blankets