Bottle Biosphere Guide Here

: Sphagnum moss or a mesh screen keeps the soil from falling into the drainage layer. Substrate

"I check on my jar every morning," says David, a moderator of the r/ecosphere community, which boasts over 50,000 members. "It’s meditation. You see a snail laying eggs, or a strand of algae splitting, and you realize that all of this is happening without you. You set it in motion, but it runs itself. It’s the closest most of us will get to watching a planet form." Bottle Biosphere Guide

The bottom of the jar is not just dirt; it is the battery. You need a layer of mineral-rich soil or sand. In the high-end "Ecosphere" brand products, this is often a gritty, volcanic substrate. In DIY versions, hobbyists use capped garden soil or mineralized topsoil. : Sphagnum moss or a mesh screen keeps