Future O. Ornatus Setup Advice?

[aspenolm]

Hello! I currently have 10 Orthoporus Ornatus' (5 sonorans, 5 texas golds), and I realize that I do not have them in the ideal setup (I have two separate tanks for 5 each, but it is still too small imo, especially for the larger sonrans) so I want to upgrade them in a couple of months to a single larger terrarium w/ some native sonoran desert plants. My main question is what would be the ideal size tank for 10 desert millipedes (I'm thinking probably 15-20 gallons, should it be more?), and what substrate should I use for a more arid species of millipede that would also be good for native plants like prickly pear and desert marigold? Should I just go out into the desert and dig for some sand and add a decent chunk of flake soil and other decomposing things? Because desert soil isn't exactly known for being rich in organic matter. Attached is also a rough sketch of what I have in mind for the tank, ignore the weird proportions. Any advice is appreciated, I just want to upgrade them into an enclosure that doesn't feel too crowded and also looks nice.

 

[Brewser]

I'm liking your plan for upgraded enclosure.
Be sure to post a pic or two when you accomplish this.
Would like to see/learn more about this endeavor.
Curious as to why mix sonorans with texas golds ?
Best Wishes for the Future.

 

[aspenolm]

I'm liking your plan for upgraded enclosure.
Be sure to post a pic or two when you accomplish this.
Would like to see/learn more about this endeavor.
Curious as to why mix sonorans with texas golds ?
Best Wishes for the Future.

Mainly, its because they're technically the same species, just different regional morphs, and I haven't read anything as to why they wouldn't cohabitate well. They have pretty much the same needs humidity wise and diet wise, and I've had other millipede keepers say they would do fine in the same enclosure. Right now they are only separated because it gives them more space. I figure even if I make a setup that's meant to replicate the sonoran desert, the texas golds will still thrive. My main thing right now is figuring out how to make the substrate work for both the millipedes and the native plants. I doubt too much biomaterial will harm the plants, but I probably can't use most millipede substrates just because they naturally trap a lot of moisture (I don't want the millipedes to suffer foot rot, and I don't want the plants roots to rot either), otherwise I'd use my diy stuff I made for my N. Gordanus.