For dry hop additions, you can just unclamp your "Dry Hop" port on the 3 port lid and drop your hops in!
You can purge any oxygen that made its way into the fermenter by doing a quick purge of carbon dioxide. You can do this by attaching the gas manifold or All-in-One PRV to the PRV port, applying 5psi to the tank and then purging pressure from the pressure release valve.
To dry hop with the 3 port lid with minimum oxygen, we recommend the following steps:
1. Have a gas manifold directly or All-in-On PRV on the dedicated PRV port.
2. Attach a valve and 1.5" sight glass to the dry hop port. Add hops.
3. Attach a 2nd gas manifold on the top of the sight glass. Purge sight glass with CO2 through the manifold. Open valve to release hops
4. Relieve pressure in the sight glass and remove sight glass.