CocoTek coconut brick is a compressed brick of low sodium coconut coir. Growers are encouraged to mix CocoTek Organic Growing Medium with an equal amount of Hydroton (clay pellets), or combined with other hydroponic media in various proportions. Our new highly-compressed and improved brick absorbs moisture more quickly, giving users the same amount of coir as our previous larger sized brick after expansion. CocoTek makes messy brick separation unnecessary. Just drop CocoTek in approximately one gallon of fresh water or light nutrient solution and allow it to expand to approximately 1/3 of a cubic foot of CocoTek coir. Try this brick and you'll be astounded!