I'm using C3 straight. So far, on my very lightest scent, an LX10 has worked but I've only gone through one candle. I like to have about 5 straight successes before I feel secure with that combo. Next, I'm going to work on my heaviest scent and get that dialed in. That should make my middle guys easier. I think I made things more difficult by trying both eco and lx but I was using what I had. I always do that to myself. I think I'll stick with LX on these little guys for now and experiment with some ECO later. I had stopped using LX because I didn't like the mushrooming but I don't seem to be having that problem in the little jars. BTW, they are just too cute when they are burning! Thanks, Deb