I have never fermented under pressure but I would like to give it a shot. I still have a bit of confusion that I have not been able to sort out through searching the forums. I know it is crucial to oxygenate prior to pitching the yeast. But as the yeast starts to create CO2 and the oxygen is depleted, at what point is the yeast cell division and growth inhibited by lack of oxygen and the CO2 being driven into the solution? Do use the spunding valve from the start of the fermentation? Went transferring under pressure there will inevitably be some slight differential pressure in the primary and secondary, does that allow the CO2 to come out of solutions and disturb the trub. What is the best amount of pressure to ferment under? I am seeing around 10 psi kicked around alot.