FC E6500 VS FC E8000

[LJ farming]

What would be the optimal height from canopy for each of these lights for flower? I’m. Currently building an 8 light room which I plan to have 4 trays 4x8 each, my current ceiling height is 8’ and it can go to almost 10’ if I remove the drop ceiling but I would loose all the insulation so probably not really an option. FastFit trays are 14” off the floor so I am roughly left with 58 inches of headroom give or take. I currently let my plants get 20-30” tall in veg so height is definitely a concern.

Also nervous about switch from HPS to LED so any suggestions are appreciated!

 

[flylowgethigh]

An 8000 is a powerful light. My tents are 8', with 12" overhead reduction for the vent sys. I lose 8" with the SWICK base. Then the soil height in bags, about 10". With LEDs you can have the plants up into the lights and not catch fire, but that is a little close. Can you make the canopy even? I am using 680 watt lights at around 75-80% power, maybe 8-12" to the tops. PAR meter will help you set power for the height. Photobio is a good one for the price. That height/power gives around 750ish to 1000 umoles with my 680 watt.

You may want to adjust flip to suit the stretch in your constraints and grow method. I bend the plants over if they get to tall. Hybrids are a good fit so far. Sativas usually need training and bending.

LED uses a lot of cal-mag, or the leaves won't have an even green color. I add about a TBSP with each 4 gallons, sometimes more.

 

[Mars Hydro Led]

What would be the optimal height from canopy for each of these lights for flower? I’m. Currently building an 8 light room which I plan to have 4 trays 4x8 each, my current ceiling height is 8’ and it can go to almost 10’ if I remove the drop ceiling but I would loose all the insulation so probably not really an option. FastFit trays are 14” off the floor so I am roughly left with 58 inches of headroom give or take. I currently let my plants get 20-30” tall in veg so height is definitely a concern.

Also nervous about switch from HPS to LED so any suggestions are appreciated!

These two lights can be 12'' to 18'' away from canopy for flower.
Will you use some CO2 for these plants? if not, i would recommend you to choose FCE-6500 to save some money.
Both lights can cover 4x8ft trays perfectly. FCE-8000 has higher PPFD. it is more suitable for CO2 growers.

FCE-6500: https://www.mars-hydro.com/fc-e6500-commercial-led-grow-light/