What tea is the best for brewing kombucha?

I've provided some teas to a friend who owns a brewery and is recently also brewing kombucha. Until now, I can conclude that scented teas and heavily smoked teas don't work well. Other teas whether in form of tea bags or loose leaf all work great. If you want to have a dark color, you should stick to black tea or ripe pu erh tea. Other teas such as white, green and oolong turn out quite light.