Help Helium cylindre without flowmeter

[heavenplzhelp77]

Hello please help I'm using two cylinders of pure helium as a ctb method my setup is in accordance with the video "dignified helium exit" which was made by a Dutch doctor i have enough helium to go for over 25 minutes at a rate of 15 liters per minute so can i make it work without using a flowmeter just like they did in the video? Please help I'm really desperate any input or information would very much be appreciated thank u in advance

 

[heavenplzhelp77]

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[k1w1]

Have you read the mega thread on this site? PPeH ?