air bleed valve suggestions for DIY Ca reactor?

[beaker020]

You need to bleed the excess air off when you first start it up and you only recirculate the CO2 in the first chamber. The second chamber, which has little or no CO2 entering it anyways, has no recirculation loop but does need to be bled off when starting up or refilling.

The John Guest fittings might work if there is one with 1/8" mpt.

Thanks
Lance