Pressure cookers: I have read the SOP on preparing agar plates. Is it recommended to have the circular pressure gauge that has a series of numbers showing you the pressure as it goes up, or is it okay to use a good model Hawkins/Tefal etc. that has the ordinary pressure regulator on top. One of the models I have seen reaches 170° C.
I am looking to upgrade what is in stock at a school that only takes 100 ml conical flasks and looks like there is no pressure seal and cannot find a manual specific for the iSA pressure cooker.