Color separation in secondary fermentation question

I’ve had a Belgian Strong Dark Ale (approx. abv 9.1%) in secondary for a month now.  It’s developing a clear separation band in colors.  In other words, the top inch is a darker brown, while the remainder (aside from the trub at the bottom) is several degrees lighter.  The boundry between the two shades is clearly delineated. Any ideas as to what has caused this?

By way of background: nothing out of the ordinary occurred during brewing or primary.  Primary was controlled at between 64 and 66 degrees F.  Secondary has been a bit different, as it’s stored in my basement storeroom.  Down there, the temperature has dropped to a range of 50 to 55 degrees F.  Could this colder temperature be causing the separation?  What is the separation?

Thanks,
Radd

The yeast are dropping out.

If it’s the yeasts dropping, the band should grow though, correct?  It hasn’t moved in two weeks.  Any ideas on how long to leave this one in secondary?

Thanks again,
Radd

I find that the yeast will also cling to the sides of the carboy while it clears.

So you might have perfectly clear beer, but you have a murky carboy.

This is nothing to be concerned about.

Leave it in secondary as long as you feel comfortable with it.  Or package it now.

A BDS at 9.1% should age well, but it can also age in kegs or bottles.

What yeast are using? In my experience Ive noticed WLP500(the Chimay yeast) takes a LONG time to drop out and clear.  I recently brewed a Belgian Tripel and it took about 2 months in secondary for it to clear up.

Time to bottle.

+1 to Joe Sr.

Check the gravity and see what the sample looks like.

Much appreciated for the information.  I’ll take a sample tonight and see what I’m dealing with.

What you are describing has totally happened to me with Belgian strains.  You just have to wait but it can take a long time to fully settle.  It can be really frustrating!

The sample remained separated in the thief-- it wasn’t simply on the inside of the carboy.  With that said, it tasted quite good at this early stage.  I’m going to let it sit for another month or so to see if it continues to settle.  Thanks again.