400w HID Lights

Hi to all, this is my first post on icmag... I am trying a couple different lights with growing to see which works best for me. Can anyone advise at what distance my 400w HID Light should be from my plants? My grow room is approx. 1.8m x 1.0m in size. I will have 4 plants that i will be moving to this room soon.

Thanks

Depends on temps. 18 inches is a fine distance. Also depends on the reflector as to where the footprint is.

I"d say start at 30" with the plan to hopefully come down closer to around 22" and even closer if possible. From the size of your room that you've posted your reflector height may be limited by the size of your room and available side lighting from having only one light source; instead of setting height by light intensity alone.

If you have some good ventilation you should be able to get a 400w to fit in that area just fine as long as the room is tall enough(how tall is it btw?). Depending on how old your plants are start a little higher like easy7 said and then bring it down lower when flowering. The room actually isn't too small 1x1.8m is roughly 3x5ft. 400w hids usually have a effective footprint of 8-9sq ft so your roughly 15sq ft room will probably need even more light if you fill it up. As a general rule you want 50w/7500lumens per sq ft. Good luck