If you want to be a wizard attach your primary to your secondary and let fermentation purge it for you.
Fermenter out to orange carboy cap on the secondary. The secondary has a racking cane to the bottom and an airlock in the other port.
Fermentation generated co2 (pure) goes out the primary to the bottom of the secondary, then fills the secondary and out the airlock. Hell attach a keg in there as well! Fermentation generates 25 times the volume of the beer produced. Free and easy. Read. “Cheap and easy” (see what I did there!?). Purging method.
Here is a video of how I purge my kegs, same idea though.
https://youtu.be/X9NdErVUnyQSent from my iPhone using Tapatalk