Humidity for a tailless whip scorpion (Damon Diadema)?

[WeightedAbyss75]

Mine were not interested in/perhaps even intimidated by, the smallest size of crickets available at the pet shop (they don't stock pinheads), so I started breeding my own supply of tiny crickets. Now I can select the perfect size. IMHO, if they'll take crickets there's no reason to offer them fruit flies.

Though I have never offered roaches, you might look into culturing a species nymphs similar in size to pinhead crickets.

How do you set up a thriving cricket "colony" if that's the term? A big container with food, water, and lots of humidity?

 

[Aquarimax]

How do you set up a thriving cricket "colony" if that's the term? A big container with food, water, and lots of humidity?

I put a quick video together a while ago showing my setup. Once video = 1,000,000 words.
There are a lot more crickets in there than you see. They actually need a fairly dry container with lots of ventilation. I use water crystals (the dry ones from a garden center are MUCH cheaper than anything at a pet store). You need a screen-covered container of coco fiber for egglaying, and as you'll see in the video, a nursery container for the hatching pinheads. You will also need a source of heat, unless the ambient temperature is at least 76 F, preferably 80+.
Here's the video:

 

[ampersand]

Is there a way to tell if a whip scorpion doesn't have enough humidity by their colour or habits (other than tending to stay closer to the substrate)?

 

[Albireo Wulfbooper]

Is there a way to tell if a whip scorpion doesn't have enough humidity by their colour or habits (other than tending to stay closer to the substrate)?

They'll cry out to you with little creaky voices... "water! please sir!"
(no, just watch for them spending a lot of time at the substrate surface)