Review on 🌿 Optimized Exo Terra BioDrain Terrarium Substrate for Aquarium, 4.4-Pound by Betsy Mitchell

Good product, I bought 3 bags which probably gave me just under 3" deep, 3" wide and 16" long. I highly recommend measuring your terrarium as one bag doesn't cover a large area. They are simply medium-sized lava rocks, 1/4 to 1 inch wide. Most of them are about 3/4 inch tall. I also bought a bag of Hoffman brand lava rocks from Revain for my top layer and most of the rocks were just over 1/4 inch and cost about $3 more too. Before you buy, find out what sizes of lava rocks you want.