Sorry i didnt realise mate i thought it was a 315 you were using, have you got a link for where i can pick up 630 like your using 40 zips wouldn't cut i have been pulling 50-80 zips with 4 600HPS i was hoping 4 315s wouldn't be to far off, 40 wouldnt kick it for me.Again i use a 630 not a 315 but the veg was 7- 8 weeks from seed and 55 days flower. Dont think 4 315s will get 80oz. closer to 40 oz. If your running hydro and co2 maby 50oz. Mine was an organic grow in a tent. Currently im in a sealed room running my 630 in a hydro coco grow and co2. Hoping for 30 this run