refill at filling station
Yes they do
Call them and ask!
no!!
No. The tanks have to be around 2000 psi.
ballpark $40
you buy new ones not refill them
it takes 1 and a half tanks.
No, you must have it refilled at a paintball field or pro-shop. You cannot refill paintball tanks from low pressure Soda dispenser C02 tanks.
A thread protector is a small, bottle like cap, that can be twisted on top of a tank. This is more commonly used on high pressured (or nitro) tanks due to the fact of how expensive they run. A thread protector does exactly what it says, protects the threads when the tank is not in the marker. Commonly the head of the tank will get nicks and bangs, which in turn can ruin the threads and strip them, which can put you out another $50.
Psi stands for Pound Square Inch, which is a measurement of pressure. What you are thinking of is HPA or High Pressure Air tanks (sometimes called nitrogen or nitro) and yes, the G3 can only use HPA tanks.
The Culligan man is the easiest way to get refill tanks for a water dispenser. Usually only costs about $20 per month. It seems that Costco and Sam's Club are now offering this service.