distance from plants? HPS 400w

[scottcc5s]

Scott,
I picked up an inexpensive laser thermometer on ebay (about $30). So I can spot around on individual colas to see exactly how hot they are. I havenâ??t had any heat stress keeping the max at 82â??84˚. Real handy for res temps and many other things too.

HMR

Thanks for the tip, I will check it out and pick one up. I have a few LED's and this is my first HPS, they run "hot". Going to do a side by side grow to see what is better. Right now I put it 18" from top of the plants, thanks again for info