Plastic vs. Glass Carboy

Thurston Brewer

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I've always heard that you need a glass carboy to ferment in, though the plastic one are far cheaper and easier to get. It occurs to me that a two stage fermenter like myself typically uses a plastic bucket type fermenter for the primary. That works fine, so why is it bad to use plastic for secondary?

The plastic used in modern plastic carboys is obviously not the same as what is used in my food grade plastic bucket, but if it's safe for drinking water, why not beer?

Anyone with actual experience?
 
I think it's an issue of porousness. Lots of fermenters are plastic. But your right, it's the plastic carboys that are taboo.
 
I've always heard that you need a glass carboy to ferment in, though the plastic one are far cheaper and easier to get. It occurs to me that a two stage fermenter like myself typically uses a plastic bucket type fermenter for the primary. That works fine, so why is it bad to use plastic for secondary?

The plastic used in modern plastic carboys is obviously not the same as what is used in my food grade plastic bucket, but if it's safe for drinking water, why not beer?

Anyone with actual experience?
I'm not sure where you are located but in my local area over the course of a couple of weeks I found 2 6 gal. glass carboys and 2 5 gal. glass carboys on Craigslist for relatively cheap...less that $30 for all 4. I just started checking daily and was amazed by how many were out there. 2 of the ones I bought had a lot of dried residue in them but they were fairly easy to clean.

Ed
 
I here plastic lets in oxygen into brew oxygenation of the Lagering beer. The PET plastic carboys are supposed to bed good I hear and less head space in fermentor. No experience here on carboys just read a lot about brewing. I go from primary 2 weeks ish straight to stainless steal keg purge out oxygen and let her lager in that. Have you herd about the Germans Low oxygen brewing interesting stuff apparently on hot side limiting amount of let's say agitation of wort and amount of oxygen entering into wort can produce some unique brews.
 
I've got 3 PET ones, and one glass one. I think I've used the glass once. I am deathly afraid of dropping that one though since I usually brew barefoot.

I did get one of those carboy harness things to help out with lifting and moving them
 
I recently dropped mine when I was barefoot. I didn't even put shoes on when I cleaned it up. Be a man! :p
 
Now that takes brewing to the next level!:p
Maybe a bit over the top but it'd be called blood sport brewing:eek:.:)

I've always had a faint fear of my dodgey DIY brew stand giving out and collapsing whilst stirring mash and receiving a whole keg full of hot 65c wort mash all over me mmm it can be dangerous molten hot sugary liquid. :eek:
 
I think there is a difference in the make up of plastic carboys and water bottles.
Do a little research but the name brand plastic carboys are suppose to keep oxygen out.
I have seen the results of someone holding a glass carboy that breaks in there hands. Not pretty. Usually takes stiches.
I use buckets for 2 weeks+ or - and then keg except for Oktoberfest which sits in glass secondary for 5+ months, covered in frig.
 
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I've aged for months in plastic carboys without oxidation. Granted that's an anecdote. A bit of oxygen can seep through the plastic but if there's oxidation, I'd bet on the headspace rather than the plastic. Or splashing. Or both. Both are sources of far more O2 than the few molecules that make it through the PET.
 

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