My fermenting issues

Here's a strange one for me; I brewed a 10 gallon batch Saturday. I had about a 32ounce yeast starter from my Wyeast 1098 smack pack. I divided up the batch into two 5 gallon fermenters, swirled up the yeast and added an equal amount to both fermenter "A" and "B." Fertmenter A started earlier, fermented stronger and fermented longer than B. Same type of fermenter and airlock on both. I guess I will know Saturday when I make a tranfer to secondary (and take a reading) if they differ greatly. If for some reason they do, should I equalize the batch, say half of A and B into each secondary? I can only think that perhaps "A" got a bit more of the robust yeast, though I thought "B' would eventually catch up, but from a visual inspection it didn't. Any ideas or comments?

Maybe fermenter A was rinsed a bit better than fermenter B? Don't sanitizers kill yeast? Maybe there was a bit of residual sanitizer left in fermenter B? Just a thought.

As for mixing them, why not just do a bit of an experiment and see if they really finish differently? See how A compares to B after conditioning?

it's not really a controlled experiment if you don't know what the difference is.

are both a and b the same ingredients? how did you equally split up the starter? perhaps b didn't get as much yeast in there...

Death Brewer, I'm afraid to answer you (do you realize you are on post 666?)

Same batch, put into 2 fermentors. Swirled up the yeast starter and put 16 ounces in each. Everything is the same, that's why I am confused. My only guess is that A got more of the good yeast, whereas B might have got more of the starter sans yeast. But wouldn't B eventually catch up to A, and just have a lag time in doing so?

Were the fermenters in the same place?

Is this based in gravity readings or airlock activity?

I do 10 gallon batches and split into 2 fermenters all the time. Usually there isn't a big difference. But there is one. Sometimes one has better oxygenation or more yeast than the other and it ferments and finishes a little different. I do notice a slight taste difference and have seen FG's a good point or more off from each other. This is the big problem with splitting into 2 fermenters. I wouldn't worry too much about it though. They will both be fine, just a little different. How can you love one child over another? They are both your offspring (or beer).

Fermenters were side by side, and the difference was on airlock activity only. I plan to take a reading Saturday at the earliest (I like to go by the 1-2-3 rule) when I transfer to secondary. I'm not too worried about it, and I believe the beer will taste fine, it is just odd how much difference in airlock action there was between the two identical beers, not only in ingredients, but temperature, aeration and equipment.
I am looking to make a single vessel fermenter out of a Sankey that I saw in another thread. This would eliminate this observation I have made.

If you were going by airlock activity, there could have been a small leak in the one. Also, was the liquid level the same in both airlocks? Less liquid in the airlock means less CO2 required for each bubble. An airlock with twice the liquid will bubble at half the rate.

The level of liquid in the airlock looks comparable, but you could be right about a slight leak in the one. I'll post here the hydro readings when I open up the vessels and make the transfer.
I rememer one time, on a single batch in a plastic bucket fermenter, I thought I didn't have any activity going, and then discovered I didn't have enough liquid in the airlock to lift the center piece! A lot of worry there for something stupid on my part.
Thanks for everyone's input.

Isn't it amazing that a fairly simple problem that probably isn't a problem at all has so many little details to try to decipher?

Even though the wort in the two fermenters came from the same batch, they may not be identical. Depending on your system, how long the wort sat before putting it into the fermenters, and if it was stirred, you may have slight differences in the composition. For example, if you have a kettle that dispenses from a outlet at the center below a false bottom such as I have, the first runnings from the kettle going into the first fermenter contain more particulates than at the end of the wort. In addition, the wort may stratify slightly so that the gravity in the first one is slightly higher than the second. Probably much more likely that it is a yeast difference than a wort difference, but the particulates being more in one fermenter than the other, especially if they happen to be rich in yeast nutrients or do something to dampen fermentation, could potentially be an issue.

stevenb said:

Death Brewer, I'm afraid to answer you (do you realize you are on post 666?)

Click to expand...

dang, missed it! but what counts is you noticed

Here's an update on my situation, though a few days late. For those not familiar with my first post I made a 10 gallon batch and split it into two carboys for fermentation. I had two visible differences in airlock activity, even though all variables seemed to be consistant between the two. When a week passed, and it seemed activity had stopped, I was ready to transfer. I took hydro readings and they were exactly the same, but only 1.030. This was from an original gravity of 1.052. I realized then what was going on. We got a stretch of cooler than normal weather, and my basement temp. was down to 63 degrees, which was a bit too cool for my Wyeast British Ale yeast. I took the batches upstairs into a warmer environment and they have resumed a nice steady visible fermentation. Lesson learned.