4 x 4 x 3 inch Growing Blocks without holes. Used as a second stage from smaller cubes, just place the small cube on top. Growing blocks are great for ebb and flow hydroponic systems or for use as mid stage for plants eventually going on to Rockwool slabs. The blocks are individually wrapped in plastic on four sides to hold moisture and stop alga growth. The base of each block is grooved for drainage. Blocks are supplied in 24 inch long tear away strips. Case of 180.

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