So I have a brown ale kegged, and its been carbonating for roughly 5 days now. To match the desired volume, I have it set at 9 PSI (CO2 tank at room temp, beer at 35 degrees F) and now that day 5 has been reached (day 6 tomorrow), I've had a few cups of brew, which mind you, turned out delicious just a little low carbonation than I was expecting.
Anyway, the problem is this. Over the course of the 5 days, I've had to turn up the pressure on my regulator a few times. The first few nights it dropped to roughly 4-5 PSI, and I had to bring it back up to 9. I chalked this up to the CO2 being absorbed into the beer, but why is the pressure not automatically increasing to match the loss? Either way, overnight into today, it held 9 PSI just fine, so I took the liberty to enjoy a couple cups. As stated before, it was a little low carbed, but I noticed that after 2 cups, the pressure dropped to about 5 PSI. I'm a little confused. Is this how all CO2 systems work, or is this a telltale sign of something wrong with my setup?
Thanks in advance for the help and advice, should anyone have the input