I know there aren't many fruit flies this time of year, but after the fruit fly incident of last year, I'd keep a neutral smelling solution(or at least stinky)like K-Meta in there. I had a prssure change and the airlock like you have filled with some apple wine from the carboy. I left it there not thinking anything ill of it. After all nothing could get in the airlock. The air pressure changed again and all of a sudden the wine went back in the carboy. When I saw that I figured I had better dump it and refill with fresh. I didn't think any more of it until 4 months later when I went to seeeten it. I found-if memory serves me correct- 5 wine pickled fruit flies! I was going to bottle it then, but I still haven't another 3 months later. I'm waiting to see if I get 6 gallons of apple wine vinegar.
I think I would double check the instructions to see if they really say to fill with wine
OMG, I'm an idiot! - I have read, and re-read, and re-read those instructions and saw the same thing everytime - not the BUNG!! ---to use to top off the carboy, water or pmb in the airlock - - - - duh - I have fixed the problem - That's ok right? using the pmb solution to put in the airlock??
Ok. you must think I drink WAY too much wine - I can't seem to type or read! I meant, that the instructions were talking about filling up the carboy to within 2 inches of the bung, with the reserve wine - and water or one of your suggestions for the airlock. Actually, I am drinking a nice Black Opal Shiraz - I can't wait, until I have all my own wine to drink!