Calcined clay is a fantastic additive to soil, promoting drainage as well as water retention, cation stabilization, and maintaining the integrity of the soil. Great for bonsai and epiphyte mixes as well as an aquarium or paludarium aquatic substrate.
Did we forget to mention? This is the BEST substrate around for incubating reptile eggs! It holds humidity and buffers water pH far better than perlite, and is reusable! Just stick it in the microwave or boil it to clean. Best of all, it changes color from light to dark when adequately loaded with water, meaning no more guesswork when it comes to checking on your eggs!!