Coco is high in calcium and a growth hormone called zeaton which is also found in corn. its a good for organic hydro as is sawdust and pine chips. Coco is best and it is a great source of carbon to help with the nitrogen to carbon ratio which should be under 20 to 1 for proper growth.(R:S ratio) Grow organically if ya can it is so much better and earth freindly. You could just get rockwool shipped in. It is so light that it would not be that much. I bet you could get it shipped to the grow shop if you dont want it shipped to you. I would use coco if you can with organic hydro nutes. O soooo good.
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