DaveO, from what I have been able to find out from some research, the mother that forms will take on an appearance that looks like a bloodclot, dark red and coagulated. I gray film comes to the top of the vinegar that is working and ultimately gets rather thick skinned. Over time, the addition of wine will cause the skin to be oxygen deprived from the alcohol and it will sort of die and sink to the bottom. It is then removed and discarded. This process, once it is up and running,is a continuous one where you draw off vinegar to give away to friends or use yourself while you are adding wine to make more product. Anyway I found a really great informative site but I am so dumb I can't make a blue clicky. I will try to send the websiter addy in a post soon.