I have never heard of one gram per watt before. You want to target 50 watts of light per square foot. As far as yield goes, there is no accurate way to predict that. Many variable are in play. Genetics, setup and style of growing, nute program and the skill of the grower are all in play. Of these, genetics play the largets role. You'll never grow a monster plant if the genetics are bad. Reputable seed dealers, found here
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