Cider in my basement-newbie

[homemadeisbest]

I have had a carboy of cider sitting for nine months. I just noticed a slight film developing on top. What could that be? Should I be concerned? Thanks!

 

[caseymac91]

Can you describe the film? or take a picture? It could be turning to vinegar. Taste a sample, if it tastes good you're good.

 

[reekbinary]

A white film on top is usually a mother of vinegar caused by vinegar making bacteria and oxygen. A small amount is harmless...and when you rack or bottle avoid that layer as best you can. If the cider is to stay in the Carboy much longer, try to eliminate the oxygen. Make sure bung is tight and airlock full.

Remedies:
- Leave smaller space between bung and cider.
- top with finished cider
- lay down co2 in space between cider and bung before inserting bung
- bottle now