I only use 24-hour lighting cycle for the first couple days after the seed germinates ... I run 18/6 until the plant shows maturity, by alternating the internodes (usually after the 5th set of branches, or so) ... then 12/12 until harvest ... some growers are experimenting with leaving the plant in darkness the last few days ... I've tried it a few different ways, can't say as I saw any difference ... :jointsmile: