Tapped a 1/8"NPT/JC fitting for 1/4" OD tubing into the 45° elbow.
After I drilled it thinking, hope it doesn't turn into a venturi port, but works okay.
Flow is slow, 20 seconds to fill 500ml and not much pressure, I can easily block it off with my finger.
BTW, I asked the pressure rating from the manufacturer, and I wasn't much help to myself (DIY reactor
).