#1 Can this carbonate non pre-carbonated drinks like tea, fruit juice, etc?
No. The simply keep tanks pressurized that will keep carbonated liquids from becoming flat
#2 Can you extend the tap to be used in a bar fridge?
There is no instruction as to how to extend the tap
#3 Does this work also with any nitrogen cartridges for cold brew coffee. also can you get hookups needed to add a co2 or nitrogen tanks to last longer
this unit is designed for beer and we cannot guarantee that it will work with coffee, wine, or other liquors. You may also use different cartridges as long as the thread will fit the unit.