You shouldn’t put HPS grow lights above your plants by more than 30 Zoll (76 cm). Medium-sized lights like 600w’s can be placed about 25″ (64cm) above the plants without losing vigor, while smaller 400w lights can only be placed about 20″ (~51cm) away from the plants.
MEHR: 7 Gründe für den Wechsel von HPS- zu LED-Wachstumslampen 2023



