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Box is correct.
Plants will survive under almost any conditions, I've grown clones hydro in 2 litre pop bottles, no air, and only 1 nute and water change through veg. The plant flowered sweet potent tiny buds - but it flowered.
Plants evolved to work efficiently using natures light and dark cycle - during the light the plant focuses on photosynthesis and during the dark the plant is MORE EFFICIENT at other tasks such as root growth and dispersing energy. 18/6 or 20/4 is a good mix for veg for most strains.
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