Upgrading lights

[Gordonb]

Hi
I have been growing with T5 florescent lights, I am upgrading to MH & HPS lights. Any guidelines as how far from the plants to hang the light and is it ok to switch lights half way through the flower cycle? And should I keep a fan on the same timer as the light? I have a 2' x 4' x 6' tent and i plan to run the T5 vertical on the back of the tent. I have grown some really nice plants with the T5 but not much luck getting any weight out of the buds.

Thanks

 

[Antics]

400w 12" 30cm
600w 18" 45cm
1000w 24" 60cm

No problems switching light types during flower, I would suggest a switch during lights on, as you do not want to interrupt their dark cycle.

You can find that, and a lot more info here: How to Grow Marijuana Everything You Need to Know

It's one of the best pages to bookmark, it's been my goto page for all of my grows so far!

 

[theengineer]

if you're running a 600w+ lamp I would strongly recommend a cooltube

 

[Tead]

if you're running a 600w+ lamp I would strongly recommend a cooltube

Me too. Cool tubes are the way to go. Easy, cheap, and very effective. I've been amazed at how the top of my cool tube reflector never warms up at all.

As far as distance... I've always just put my hand near the top of the plant to feel the heat. If it's hot on my hand, then I raise the lights. Not very technical, but it's worked for me.

 

[theengineer]

I had plant tops within 6 inches of a 600w HPS, and they absolutely loved it tbh, they are definitely the way to go with HID lamps for sure