Stainless Wort Aeration Carbonation StoneUse this stainless steel stone to aerate chilled wort prior to fermentation or for carbonation after fermentation. For aeration, after removing hot break out the bottom port once wort is chilled, simply sanitize the stone and bottom valve on the fermenter, then attach the stone and open the valve. Oxygen will pass through the 2 micron pores and diffuse into the wort. Recommended aeration period is about 1 minute for 40L 10gal batches at a flow rate of