Just don't want to tie one up with mead, especially my first batch - I only have a few. And I have some of these aging belgians/barleywines.+1 for corny keg. Thats what I age my belgians in. Why don't you want to use one?
Reason for asking about the FZ is that I went to a stainless unitank a little while ago. I have the FZ conical unitank sitting around collecting dust. I can buy a corney, or a glass fermenter, but figured if the FZ could prevent O2 ingress, then it would be able to be used for something. Just trying to save money and prevent wastage.
Seeing that the FZ I have is sold as a unitank, meaning it can be kept for serving too, I wondered what that meant for capability to maintain gases where you want them (ie CO2 in for serving/carbonation and O2 out) in the longer term. As noted per the KL FZ unitank website - "Uni tanks are conical fermenters used both for fermentation and for carbonating and serving finished beer."
Being sold as a unitank for serving, that would indicate a certain period (I would expect adequately long - maybe a couple of months - but that depends, I guess, on how quickly you drink it!) that it will prevent gas exchange. If it is overall fairly permeable to gas in that time, then I can't see that it is particularly useful as a serving unitank. That is, unless you are going to smash your batch within a very short period of time. I never tried it for serving, only used it for carbonation/pressure ferment, then transferred to the corney for serving.
That is why I thought I'd ask in this thread - so the KL guys could answer with some technical information. I appreciate the suggestions, but was after that more specific answer, if they are available.