grow light height

Starting a new grow with this light in a 2x2x4 and have some questions https://www.amazon.com/dp/B087JKDVTF/ref=cm_sw_r_cp_apa_glt_fabc_KG0K7211VMC5H4KA9BNP?_encoding=UTF8&psc=1 They show the hanging heights and the given ppfd levels... my only question is are they assuming that the light is...

Day 3 seedling Auto Sweet Critical & Auto Northern Lights in a 2x2x4 grow tent.Using a Mars Hydro TS 600. I know what Mars Hydro recommends, but was wondering if the light is to close at the presentation moment. Its 21 inches from top of seedlings with dinner as low as it can go

Okay so I want to grow a GG#4 feminized photoperiod however im not sure how tall they grow. Also, im not sure if i'll have space to hand my lights 24 inches away because my tent is only 80 inches tall. I could upgrade to a gorilla grow tent with the 1ft extension if need be but im not sure if...