Berry volume

[JohnFrum1978]

Just starting a blueberry melomel. I've got 15 pounds of honey, 10 pounds of blueberries in a straining bag, some yeast nutrient and irish moss. The plan was to remove the berries in two weeks, let it ferment out, then move it to a secondary with another five pounds of blueberries.

When I remove the blueberries from primary It seems like I'll lose some volume. Am I okay at that point to add some water to bring it up to five gallons?

 

[biochemedic]

If you're still actively fermenting, I personally think that you'll be OK with the extra headspace -- the production of CO2 will fill up that headspace and protect the surface of the mead (CO2 is heavier than air and will displace most if not all of the oxygen upwards and out the airlock).

As an aside, this is one of the reasons I brew 6 gallon batches -- so if I am going to require a transfer to secondary, I can then go from 6 gal to a 5 gallon carboy, and many times still save an extra bottle or two for later topping off...

 

[MedsenFey]

Yes, you don't need to top up during active fermentation, and it might even lead to an eruption. You'll be adding more volume with the juice from the berries soon also.