I have done several Brett beers, both with Brett as a Primary yeast, and some with Brett as a Secondary yeast. When using it as a Primary yeast, it has been 3 to 4 months in the fermenter before bottling. When using it as a Secondary yeast, it has been left for about 12 months before bottling.
I have primed the same way I do normal ales.
I find all the beers are carb'd, taste great, but do not form much of a head (if any). The beers are not flat.
There is obviously yeast available as none of the beers are flat. I have been using between 5 to 5.5 ozs of cane sugar for priming 6.5 gallons.
My Pale Ales and Belgians carb really well, form a decent head when pouring and keeps it all the way to the bottom of the glass.
I am wondering if the long time in the fermenter is the reason for the relatively low carbonation. Due to the long time sitting in the fermenter, the entrained CO2 is less than assumed for a normal beer.
Should I be using more priming sugar due to the long time sitting? Is there any way of figuring out how much entrained CO2 is lost over time?