This is the method I have been using to grow lettuce indoor with very limited space. The lettuce can be harvested multiple times.
My Indoor Setup: https://plus.google.com/118382364204627409312/posts/5Cr9CWGsoDG
After 3 harvests: https://plus.google.com/118382364204627409312/posts/ebxccnugd6t
Harvest Lettuce 6 Times: https://www.youtube.com/watch?v=Ywgq4vFpJck
General Hydroponic Nutrients(Flora Series 3 Parts):
1 Gallon of water, pH is between 5.5 – 5.9
5 ml Flora Micro
5 ml Flora Gro
5 ml Flora Bloom
5 ml Cal/Mag
video source: www.youtube.com
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