As I wrote…I'm now trying 2 different clay/perlite mix.
One layer of clay on the bottom and one on the top for both, difference is in the middle, where one is a mix of perlite and some clay pebbles, and the other one is 100% perlite.
Here the clay layer on the bottom
Here the clay layer on the top
Here the ''middle'' part of the 100% perlite
And here the ''middle'' part of the mixed medium
At now, cuttings are vegging and they're fine. No noticeable difference, they just grow fine. Have to wait a couple of months to know more.