How far away should I keep the led light from the top of my plant. Currently I am about 25" from the top my plants, I am using two 150 true watt leds. One of the lights is I believe the older Mars hydro 300 and the other is an eBay 300 watt equivalent, alot more purple/red than the Mars hydro. On the Mars Web sites it suggests between 24"-30" for all of there newer lights, should I leave my lights at 25, or raise them a little bit?