Omega Air Cylinders

Simple answer is NO. Pressure will just equalize in both tanks. Example: I had 4300psi in my guppy and 3900psi in my tiger shark. Hooked together and opened valves. Now I have about 4000psi in both tanks. You could make a fitting that quick connects to your fill line to place a check valve in front of the small tank, but not sure it would be worth the effort as you will only be able to top off the small tank a few times from the big tank I would assume.