I have 2 six gallon batches of niagara wine going. The S.G. is .990 and the temp. is 68. I racked the wine 9/27/11. I will need to rack again 11/27/11. My question is, before the last racking and now the wine is starting to clear but the top 2 to 3 inches is dark and the rest of the carboy is clearing. Is this something to worry about or will this all clear in time? I never sean this before. thanks.