carboy questions.

I recently purchased a 6.5 gallon carboy that I plan to use as a primary and I also purchased a 6 gallon PET carboy. My question is will the 6 gallon be to big for secondary? Can you have to much headspace in a carboy that will affect the beer? Also when transfering to a secondary does it hurt anything to keep it in the primary like the directions say or do you need to transfer as soon as the krausen drops?

Three weeks minimum in primary then bottle or keg. No need for secondary unless dry hopping, adding fruit, oak chips, etc. Be sure to take a gravity reading to make sure it's really finished.

If you do secondary (I mean actual secondary fermentation where you add fermentables to the brew to feed the yeast or if you're dry hopping) then the 6 gal bottle will be fine, since more CO2 will be produced. I'd use a blow-off tube, though, just in case things get really active. Otherwise, there's no need to use a secondary. You'll still get clear beer and you won't get off-flavors from sitting on the yeast cake.

The 6 gallon secondary is not too big.
You can leave it in the primary for a long time without causing any harm. Most leave it in the primary 3-4 weeks, then only use the secondary for dry hopping or adding fruits.

Agree with the above posts....unless you're doing anything in addition to just letting it ferment, don't bother with a secondary. The headspace shouldn't be issue if you transfer correctly, however the least amount of headspace possible would be preferable.

Thanks for the help. This is only the 3rd batch I have made and i have always followed the schedules. This one calls for 2 weeks primary 2-4 weeks secondary and bottle for 2-3 weeks. Maybe i will leave in the primary for 3 and bottle for 3.