Thank you Stefan!

Eric, you can go as far as your budget or your interests take you with this. There are equal numbers of folks who generalize the soil and grow good plants, and then there are those who try to duplicate the soil of the localities ( IIRC, Ech range from Oklahoma to Arizona and deep into Mexico). Most specialists would, I’d guess, take the more difficult path of using an improved soil.

Most important for succulents is the drainage. Well draining and quite grainy /gritty mix should be just fine for most. Differentiate in using more or less acidic soil: some cacti like more limey soil, most would prefer slightly acidic, or neutral mix. IIRC, your plant is in the second group. It is prone to rotting, and, if available, use rain water.

I generally use some mixture of commercially prepared cactus & succulent “soil” (roughly 30 to 40%) to which I add pumice (60 to 70%). That seems to work well in my location for my plants. Those are very rough percentages as I generally eyeball it. In no case, though, is the pumice less than 50%. As the pumice tends to be dusty I do always rinse it in a sieve first. If I can find chicken grit (and not being lazy) I will throw some of that in too, also rinsed first.

Thank you all for your help!

My weather is wet and humid. Thinking about not using anything but minerals. Is there anywhere I can see a list of additives people commonly use?

Pumice, grit, perlite, scoria, turface, zeolite...whatever you can find. I use 1:1 mix of grit and sifted perlite, with small amount of turface (maybe 10-15%).

There is inorganic, ready made mix available, LechuzaPon. It contains zeolite, German washed pumice, lava and some fertilizer. I never used it, but some ppl here do.

Thank you Rina you've been a big help!

Eric, go to a feed store and get poultry grit, which is granite. Don't get poultry scratch, which has animal feed in it.

Thanks! Very familiar with grit I used to have chickens. I'm from KY haha.

If you can find the grit, use it, in varying proportions, with Turface MVP (there's a locator box on their webpage to find your local distributor - I'd guess the grit, the Turface, and maybe a little sieved garden soil and you'll be on your way to having an E. reference collection.