Grodan Gro-Block Improved Medium 4" GR7,5 w/ hole (4x4x3") (WRAPPED 6/strip 32 strips per case = 192 blocks per case) 4' x 8' 1 GPH and the fine

1 GPH and the fine droplet size

5 in poly air tubes

Replaces a 1000W HPS at roughly 40 percent less energy with the dialed-spectrum advantage

Maintaining this symbiotic relationship early in the season allows crops to establish quickly

match it to appropriate sized filter

Grodan Gro-Block Improved Medium 4" GR7,5 w/ hole (4x4x3") (WRAPPED 6/strip 32 strips per case = 192 blocks per case) 4' x 8' 1 GPH and the fineGrodan Gro Block Improved Medium 4" GR7,5 w hole (4x4x3") (WRAPPED 6 strip 32 strips per case = 192 blocks per case) Introducing the Grodan Gro Block Improved Medium 4" GR7,5 a breakthrough in horticultural substrate design. This state of the art block is meticulously engineered, keeping the evolving needs of modern growers in mind. State of the art Density & Hydrophilic Technology: The Grodan Medium 4" GR7,5 is the embodiment of sophisticated design