From
http://www.eyehortilux.com/products/High-Pressure-Sodium#shps
wattage | intial lumens | lumens per watt
1000w - 145,000 - 145 lumens per watt
600w - 88,000 - 146.66 lumens per watt
400w - 55,000 - 137.5 lumens per watt
250w - 30,500 - 122 lumens per watt
So were looking about 1600 lumen difference 600w vs 1000w.. That's like a 25w cfl.. Pretty negligible to me.. Though I understand the benefit of using 600w lights when going a couple kw.. better canopys and stuff
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Good to know you guys are getting to like a ft from your canopy with no problems. I can't raise my light any further, but they seem happy so I'm just letting them go
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