[Antennaware] Grounding needs

[Howard W3CQH]

I live in a 1 story home with a accessible attic.

I have an Icom AH-4 tuner mounted in the attic, and need to run a real 
ground to the 8' ground rod we just pounded in.

My question is - should the ground wire coming from the AH-4 be of a wire 
gauge of #12, or should I consider running 1/4" copper tubing?  The total 
length of the run is approximately 30'

73's