Back in the day, we used to just sell lamps based on the overall Lumen output thinking, the more lumens, the better!

This is not the case at all, as lumens are for humans and we need to understand PAR, PPF, power loss and most importantly PPF ef cacy. Do not confuse the word ef cacy with ef ciency. PPF Ef cacy is a unit of measurement used to score the output grow light intensity vs power consumption.


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