Satellite Fermenter

The instructions that came with an ingredient kit I am using (IPA) recommended using a satellite fermenter to avoid having to unseal the primary fermenter for measurements. After a week, the brew in the satellite fermenter was reading 1.016. However, the airlock was still bubbling fairly frequently (once every 4 seconds or so) which led me to believe that something was up with my reading.

I took a sample from the primary fermenter, and sure enough it was reading 1.022.

Does anyone have an opinon on using satellite fermenters? A search of this forum didn't bring up any mention of one, and none of the books I've read so far recommend using one. I'm guessing it's not a widely used practice?

I've never heard about it, although that doesn't mean much. I've never had any problems with sampling, although I really only do it at racking and keep an eye on my sanitation measures. A satellite fermenter sounds a bit like a waste of wort to me.

I have never heard of this either. The only benefit I see with a satelite fermenter would be not to possible contaminate the primary fermenter when taking sample readings. IMHO I think that there are two many variables to take into account with two fermentations having the same readings. Yeast count, temp, etc. that would make the smaller ferment differ from the primary ferment.

I've never used one except to force ferment part of a stuck batch. I'll draw off a pint and pitch 10 grams of distiller's yeast, give it a good shake and warm it up to 80F for a day or two. Whatever the SG is at that point is the best you can hope for.

I think what they mean is usually called a force ferment test. This is actually not so much for taking readings and correlating them to the actual fermentation but a means of determining the FG in order to be able to find oht how low the actual fermantation should go. In order to prevent this fermentation to get stuck as well, it is kept warm and can be aerated at times. It's important that you use the same yeast since the attenuation of the yeast factors into the FG. Simply take 1qt of your wort after pitching and aerating and let it sit in a warm place. This is a common tool when doing high gravity beers which can be prone to stuck fermentations.

I've never done one but plan to do one when I brew a Doppelbock next weekend.