How long will it take do you reckon for my coopers kit which is brewing at about 15 degrees to finish. It says on the packet that fermentation couold stop all together if it got below 21degrees. Will it still ferment? if so how long will it take?
Which kit are you using, the bavarian lager and pilsner are both supplied with lager yeasts which will work at lower temps. If using the ale yeast that comes with the lager,real ale,stout, pale/sparkling ale ect. then 15 C is a bit low. It will take a couple of weeks to reach final gravity. Try wrapping the fermenter in a sleeping bag/blanket, fermentation generates a small amount of heat. I think that maitaining 18 C will esure complete fermentation. Might be a good idea to choose a yeast that is comfortable at the temps you plan to brew in.