Thanks! I didn't realize you could buy directly from Innokin. It's interesting that I read on one site that the Ajax coils are compatible with Zenith tanks, but on Innokin's site, under Z coils or Ajax Coils, it tells what tanks coils are compatible with, and it doesn't say under Ajax coils that they are compatible w/ Zenith. I also found this chart which gives the recommending base mix ratio, wattage, etc for each coil. 70/30 should work fine (so they say) I will say that the last time I bought 3 (5) packs of 1.6 ohm and I'm still on the first box (with one left, I think) and I washed my tank, dried it and started a new coil yesterday. This coil I have now is amazing. I didn't dilute or cut the 70/30 in any way except for adding a few menthol drops. It says hydrated and each puff is wet and flavorful.......The last few I've used this was not the case......I felt like it was a struggle for it to keep the coil hydrated with my vaping style, which I haven't changed. I do remember this: the last few coils I used, they are push to fit, then turn so they are aligned correctly before screwing the bottom on. Usually, they slide in decently easy, but the last few, I felt like I had to really push them in hard. So I may have had some crappy coils that coincidentally happened at the same time I switched to 70/30.