Use this substrate as the base layer in your bioactive setup to aid drainage and biological filtration of your terrarium water. Natural, non-organic substrate Prevents waterlogging of soil Will not decompose ensuring longevity Ideal for a variety of bioactive setups How To use Bio-Drain This superb substrate is ideal for use in a wide variety of bioactive setups. Simply rinse before use then spread over the base of your terrarium. Add your draining mesh and top substrate then decorate. Why You Need Draining Stubstrate This naturally occurring gravel allows water to drain freely from the soil into your reservoir and vice versa, ensuring your soil doesn't become waterlogged. This is important as too much water in the soil can prevent air movement, rot plant roots and lead to a build-up of unwanted bacteria that can be harmful to the inhabitants of your terrarium and cause unpleasant odours.
