Exo Terra Bioactive Terrarium Substrate, 2 kg Volcanic Soil

Exo Terra Sub Stratum is a natural substrate for bioactive planted terrariums, supplied in a 4.4 lb (2 kg) package.

• Volcanic soil from the foothills of Japan’s Aso Volcano — brings mineral-rich substrate to a terrarium setup.
• Porous composition supports drainage and aeration — helps maintain suitable moisture conditions.
• Crumbly, lightweight texture supports beneficial nitrifying organisms — contributes to an active terrarium ecosystem.
• Biological activity breaks down organic waste — helps keep the terrarium environment clean.
• Designed for planted bioactive terrariums — provides a base for plant and animal life.

Building a planted terrarium involves balancing moisture, airflow and the needs of its living inhabitants. Exo Terra Sub Stratum is made for bioactive setups where the substrate can support plants and beneficial organisms as part of the terrarium environment. Its volcanic-soil composition and porous structure make it suitable for setups that need drainage as well as moisture retention.

What is Exo Terra Sub Stratum made from?

It is natural volcanic soil composed of andesitic and rhyolitic tephra from the mineral-rich foothills of Japan’s Aso Volcano. The soil contains abundant nutrients that provide a foundation for plant growth in a planted terrarium.

• Andesitic and rhyolitic tephra form the substrate’s mineral composition.
• The naturally nutrient-rich soil is intended to nurture terrarium plants.

How does the substrate help manage terrarium moisture?

Its porous composition allows drainage and aeration, supporting moisture conditions suited to plants and animals. Drainage helps prevent waterlogging, while airflow through the substrate supports root development.

• Drainage helps keep excess water from pooling in the substrate.
• Aeration supports developing plant roots.
• The substrate is intended to maintain proper moisture levels for terrarium life.

How does Exo Terra Sub Stratum support a bioactive environment?

Its crumbly, lightweight structure provides conditions for beneficial nitrifying organisms to establish. Active biological processes break down organic waste and help eliminate ammonia and unpleasant odors within the terrarium.

• Beneficial nitrifying organisms can establish in the substrate.
• Biological activity helps manage organic waste, ammonia and unwanted odors.
• The substrate supports an environment for both plants and terrarium animals.

Exo Terra Sub Stratum suits terrarium keepers creating planted bioactive environments for plants and animals, especially setups where drainage, aeration and biological activity are important. Its volcanic-soil base combines plant-supporting nutrients with a structure that supports beneficial organisms and waste breakdown.

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