---
title: Fine clay pebbles in a terrarium | Glass Jar Garden
description: Fine clay pebbles: Small expanded clay balls sized for shallow jars. In the jar it has holds water 16 % by volume, pore space 80 % by volume, weight 400 g/L.
url: https://glassjar.garden/guide/soils/clay-pebbles-fine/
---

Soils and layers

# Fine clay pebbles

Small expanded clay balls sized for shallow jars.

## What the simulation uses

- Holds water: 16 % by volume (Water it keeps after draining; the rest runs down to the drainage.)

- Pore space: 80 % by volume (Room for air and water between grains; low means roots suffocate when wet.)

- Weight: 400 g/L (How heavy a litre is.)

- pH: 6.5 to 7.5 pH (How acid it keeps the soil.)

- Mould risk: none (How much fresh food it gives white mould; high-risk soils fuzz over in the first weeks.)

- Nutrients: low (Plant food it brings.)

- Presses down to: 97 % of its loose depth (How far pressing can pack it, keeping its weight.)

## Description
Small expanded clay balls sized for shallow jars. They drain freely and wick a little water back up.

Also called mini LECA.

Estimated, where sources were thin: values estimated from hobby and horticultural references; not measured.

[Grow it in a jar](https://glassjar.garden/?guide=soils/clay-pebbles-fine)

[Dried long-fibre sphagnum moss](https://glassjar.garden/guide/soils/sphagnum-dried/) · [Horticultural charcoal](https://glassjar.garden/guide/soils/horticultural-charcoal/) · [All soils and layers](https://glassjar.garden/guide/soils/)