It looks like the OP made his mind regarding moving to a secondary, so let's answer the questions:
If you squeeze the stopper to let air get in, you will not have anything coming back from the airlock.
I always take a reading from the fermenter before transferring to secondary or bottling. From the primary, I sometimes just drop the sanitized hydrometer in there, but reading it is not really accurate. It will give you a good estimate though. But I would recommend using a thief (sanitized as well): just put you hydrometer in the thief, dip the thief in the fermenter, take it out to take a reading, and empty it back in the fermenter.
From a carboy, I always use the thief method. You can also use a turkey baster to take a sample, but I would not put the beer back in the beer in that case, as you will have to transfer the sample in another container to take the reading => oxidation + contamination risk increase.
It looks like the OP made his mind regarding moving to a secondary, so let's answer the questions:
If you squeeze the stopper to let air get in, you will not have anything coming back from the airlock.
I always take a reading from the fermenter before transferring to secondary or bottling. From the primary, I sometimes just drop the sanitized hydrometer in there, but reading it is not really accurate. It will give you a good estimate though. But I would recommend using a thief (sanitized as well): just put you hydrometer in the thief, dip the thief in the fermenter, take it out to take a reading, and empty it back in the fermenter.
From a carboy, I always use the thief method. You can also use a turkey baster to take a sample, but I would not put the beer back in the beer in that case, as you will have to transfer the sample in another container to take the reading => oxidation + contamination risk increase.
Enter your email address to join: