VitaLink Clay Pebbles offers strong structural integrity and good root aeration. They have a very stable EC and pH, meaning they will not significantly affect the pH of your nutrient solution, or leak undesired minerals into it. VitaLink Clay Pebbles have a lower bulk density, which means they are more porous, therefore they will hold more air and water in a given volume of pebbles. The pebbles also come in irregular shapes. As they are not completely round, it means they have a larger surface area for the plant to benefit from, unlike more rounded pebbles where the surface area is smaller. VitaLink Clay Pebbles are ideal for flood and drain, multi–pot and drip-ring systems, as well as support media for deep water culture. They can also be used to mix with other substrates to improve structure, or to add a drainage layer in the bottom of pots.