Sounds like you’re off and running 
Keep studying, that’s the most important part in my opinion. And I don’t know if it was a typo, but my recommended ratio is 2:1:1 (akadama, pumice, and lava).
I haven’t had any issues with PH levels, so I wouldn’t worry too much about Kanuma. Unless your water is really hard (basic), then you should be okay.
I would like to see your tree when you feel like sharing a picture or two of it! Have fun!