Yes, you can do it at home! You say you have a nitrogen tank (note that beer gas and nitrogen are different)
Anyway, if you’ve got a nitrogen filler then fill that tank… and, assuming you’ve got some co2, leave it on co2 for a “lesser” amount of time and at a lower pressure. As the keg dispenses, you will need to put some co2 in but not much… don’t forget you’ll have to purge the keg as the nitrogen should be on higher pressure (30+psi) compared to the co2 10psi… again, depending on your situation (line length, temp, what you are serving, etc).. so, yes, you can do it yourself! F’ beer gas! It’s a gimmick! And now you can control your co2!
But, best bet would be to get a gas blender (around $1,500)… cheers!
-While trying to order she said: We aint got no roast beef, wes a broke Arbys!