Portable keg CO2 absorbtion

[Sandimas]

I've got one of those portable 10L kegs fed with 16g CO2 bulbs, Dark Farm as it happens, but they seem generic with many different brandings, and well-made. I've just put my 2nd brew in it.

All the instructions I've read say to set at 5psi for serving or 20psi for force cabonating, indicating you can have one or the other. I brew mainly British ales so mine is set 5-7psi for serving. But the pressure in mine drops very slowly (e.g. overnight) and I keep needing to top it up with CO2 (I turn the regulator off between top-ups). It's not a massive drop, say 2-3 PSI over 12 hours, I'm just wondering if that's the beer absorbing the CO2 or whether I have a tiny leak? Given the quality of construction, I wasn't expecting any leaks with these. The keg is sat in a coolish room around 15C.

 

[GeorgieV]

There is an easy check - spray some soapy water and look for bubbles.
On the other hand, CO2 absorption is also likely. The instructions given are very general. You can use a carbonation chart to workout what are your equilibrium parameters but it isn't very straightforward as the equilibrium changes every time you draw a pint. If there are no leaks, I would leave the gas connected constantly. At 7 psi and 15 C the beer is likely not absorbing enough CO2 but this is just my wild guess here.