Ok, so I’ve racked to secondary. 5 gallon carboy. I know that I was under 5 gallons in the 6.5 primary (mis-read my mark) and of course there is loss when transferring to secondary. Any guesses on how far off the 5 gal mark I am based on this Northern Brewer standard glass 5 gallon carboy? 1/2 gallon off? Too late to add makeup water, or just roll with it? FYI, this is wootstout.
Not sure on the amount but I would not add water to it now.
With my glass carboys, it usually takes about 5.5 gallons to fill it up to the neck. Just a rough guess, I would say there’s 4-4.5 gallons in that carboy.
If you do decide to top off, it would be best to use distilled water from the store as it shouldn’t have a lot of oxygen in it and should be sanitary.
[quote=“porkchop”]With my glass carboys, it usually takes about 5.5 gallons to fill it up to the neck. Just a rough guess, I would say there’s 4-4.5 gallons in that carboy.
If you do decide to top off, it would be best to use distilled water from the store as it shouldn’t have a lot of oxygen in it and should be sanitary.[/quote]
Thanks. I’ll probably leave as is… AND, mark my carboy after I bottle this stuff. 
Tony
It might not be the exact same as yours but here is my 5 gallon carboy with gallon markings by weight. I would say around 4.25 gallons.
