Yes looking for best deal on good carbon and possible other that will work in a pinch.. sens all of these companies want to gouge on prices looking to see if anyone knows a company that's fair and hasn't gone crazy yet?
I only run cac carbon when I run it. Used to run rox brs gac but it depleted too much trace. I imagine in a pinch you can use whatever inexpensive carbon you want as long as its flushed out properly.