Koelsch conditioning

My 3rd batch is a partial mash Koelsch. Boiled 3 gallons and added 2 gallons of cold water. OG was 1.042 at 60 degrees. The wort has been fermenting nicely for 3 days at 68 degrees. I bottle condition. I planned on leaving in primary fermentation for 10-14 days and secondary for 2 or 3 weeks. My question is about the proper temp to use for secondary fermentation. I've read to go as cold as 40 degrees but how would that impact the yeast and carbonation during bottle conditioning? Should I use a higher temp during secondary ferment so the yeast will give better carbonation when in the bottle? Any advice will be greatly appreciated.

there will be sufficient yeast even with colder temps, especially if you're using a kolsch strain.

if you're absolutely paranoid, you can add half a packet of dry yeast at bottling time without changing the flavor of the beer. I still think its unnecessary.

I had a LOT of trouble with the Kolsch I tried - literally everything went wrong. John, my LHBS guru was forced to try a bottle to tell me where my error was, and he just couldn't pin it down: it was skanked, oxygenated, the temperatures were off, there was an infection, AND I picked a bad recipe. So tip of the hat to you for brewing the style that I'm STILL afraid of!

As for fermenting temperatures. . . Kolsch is often advertised as a hybrid style that can tolerate higher temperatures. The truth is - in my OBSERVATIONAL and not PERSONAL experience - that GOOD Kolsch is brewed at ALMOST lagering temperatures. Higher temperatures result in weird off-tastes. So yes - get your temperatures as low as possible, and the yeast will stay happy.

As for carbonation in the bottle: don't worry about it. Plenty of yeast will make it into the bottle when you rack. If you keep the temperatures TOO low, the yeast will become dormant and, when you try a bottle in two or three weeks, it'll be flat. If that happens, just raise the bottle temperatures by ten degrees, and try again in a week. Keep raising the temperature until the yeast wakes up. So, in short - even if you don't believe me/us, you won't be hurt by trying the lower temperature fermentation. But if you go with the HIGHER temperatures. . .

I'm normally an IPA kind of guy but I've been obsessed with kolsches lately and so I've brewed up 2 batches. The first one is extract and primary fermentation was in the low 60's for 2 weeks and secondary was 34F for another 2 weeks. SG dropped one point during secondary. I just bottled it this past weekend so I'll let you know how it turns out in 3 weeks or so. The sample tasted great.

The first batch was actually more of a starter for my second batch which was AG. Fermentation took off within 3 hours. It spent 2 weeks at 64F. Temps spiked to the low 70's for a couple of days during thanksgiving wknd so I hope that didn't have any adverse effects. We'll see. It's sitting at 34F right now and I'll probably let it sit there for a couple more wknds.

From what I've read, it should be anywhere from 58-64F for a couple weeks, then drop the temps to the low 30s for a couple more weeks. Of course this only applies if you're using a kolsch yeast strain.

Thanks everyone. The fermentation container is actually 3 degrees warmer than the house temp. (68 degrees and 65 degrees respectively). I used Kolsch yeast. Temps outside in the garage vary from mid-30s to mid 50s right now. Airlock is bubbling an avg of 6 times per minute so still not quite finished.
What do you think of this plan - When primary ferment stops put it out in garage for a few weeks. Then bring back up to house temp two or three days before putting into bottles to wake the yeast back up. Saving for a fridge but right now don't have one.
I appreciate your advice to a new brewer.