How do you keep a moisture gradient in the soil for larvae? Is a horizontal or vertical gradient better?

I'm raising *Eleodes veterator*, a very small species that inhabits coastal sand dunes in Texas and Louisiana. There's not really any information out there about them or their larvae, so I'm assuming its similar to other members of their genus.

So far I've seen them eating apples and cat food, and I'm fairly certain I saw a female laying eggs. The substrate is half coco coir and half dune sand I collected and baked. They have baked live oak leaves and cholla wood to hide in. I'm hoping to see larvae soon!

hey guys, i recently got into beetle keeping and i have a bunch of larvae on hand. As i would like my maintenance to be as low as possible, i have chosen to get finished flake soil which costs about 3usd per 4L. People have reviewed the flake soil, successfully raising their larave into imago, however i would like to know if there's anything i can do to optimise or improve the quality of flake soil any further at this stage.

I also noticed the hobby is not as popular in english speaking countries as compared to asia, where many specialised beetle content is in their native language - mainly Taiwan & Japan. Are there any good sources for raising beetles? low maintenance is a priority for me - did i get into the wrong hobby? Any comments or advise is appreciated!