As I said this is my first brew, but I have been researching like mad in order to prevent any potential mishaps.
Nonetheless, I've got a problem.
Yesterday, I transferred the brew after a week in my plastic primary to the glass carboy secondary. This morning I noticed a ring of what appears to be mold on the inside of the neck of the carboy, right below the bottom of the stopper. I don't see it anywhere else in the secondary; the brew looks good.
I am going to transfer it to another sanitized carboy, but don't want the same thing to happen again. I read somewhere that mold could be due to airborne mold in my house. How do I find out if that's the case, and if it is just don't use a secondary?
Any suggestions on what I did wrong? Is the brew spoiled?
Appreciate any input