I recently started using a chest freezer with a 2 stage temp controller. I have a batch thats been in for a week and im brewing another one today. They are both APAs with same ferment temp. I am using buckets so its hard to have the probe sandwiched inbetween the buckets due to the graduated shape and the rims around the top. I'm wondering if it would be better for me to tape the probe to the new batch or to leave the probe taped to the week old batch. Im thinking id rather have the week old batch drop a few degrees than have the new batch start fermentation a few degrees high. Let me know if anyone has had any experience with this. Thanks!

If your first APA has had a good clean week of fermenting at proper temps, depending on how warm your house gets you could always take it out of the chest freezer and let the temps rise to 70F or so. This will not only help the yeast finish off and attenuate properly, but will also help to speed up the yeast in cleaning up any remaining diacetyl or acetaldehyde produced during the initial fermentation. Do not worry about any higher alcohols (fusels) being produced at this stage as your yeast has already completed its growth phase.

Then you could put the new APA right into the chest freezer for proper temp controlling.

exactly what he said

Thanks for the reply. I just taped the probe to the new batch and left the other one in the chest freezer. My house isnt warmer than 65 and overnight will drop lower than that. Were just hittin low 70's right now up here. Cant wait to try my first temp controlled/all grain batches.

In the future I would just try your best to get the newer batch at or lower than temp. Ice packs or water bath, forcing it to come up to temp rather than down.