can't sure about this, maybe you need write email to the seller, as our LEDs, we recommend 24-30iches for germination and 18-24inches fro veg, and 12-18 inches for flower.
Ahh, usefull as well undoubtedly.. I'm very interested in the mars 2 900 for my flower tent... any info other than the Web site, personal experience perhaps?
actually if you ask me i think i will say it's very good or something like that, maybe you have to ask me some specific questions, then i can know how to answer you, lol