Quote Originally Posted by Jdog7000
Make sure you got a fan blowing up on the bulb.

this is very important AND WILL ALLOW YOU TO GET THE ULB CLOSER TO THE TOPS OF YOUR PLANTS.. THIS IS VITAL FOR LARGE DENSE BUD GROWTH...

ooops caps lock.. LOL

It really depends on how many plants yu are growing under that 400 watt bulb and what strain...

If you are growing 1 or 2 plants you can let it get a bit taller.. maybe 20-24 inches...

If you are growing 4-9 plants then maybe 12-16 inches tall...

If you are growing.. 10-100 plants.. flower then with 3-5 nodes (6 inches tall)

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