I'm starting to plan out a perpetual grow and have been looking up lighting once more. I have a 4x8 tent with 3 cool tube 400 watt hps lights right now. That's only 37.5 watts per square foot. Most people say to stick around 50 watts per square foot, especially if heat/ventilation is not an issue. I was thinking of adding a fourth 400 watt to the room to bring the lighting to exactly 50 watts/sq ft. My main question is how will 1600 watts compare to 1200 in terms of yield/quality/penetration? It's about $20 more per month to run and heat/ventilation is no problem at all. My second question is how will (4) 400 watt lights spaced out more evenly compare to (2) 1000 hps lights in a 4x8 tent?
I'd take the 3x 400w Mh over 2x 1Kw lights anyday,... just for the flexibility alone, least when the power bill comes, you may turn a light or 2 off, just till your courage returns ...lol Tho I prefer to grow with 600 watters, 400w HPS does the same -ish area ie. 1 square yard or metre, holding 9 plants in 3 gal. pots to 3ft high in 3 months, the 400w lights tho 1/3rd less need to go that extra week or so depending on strain, and type of bult at this level makes a big difference too, google that! Include the 4th 400w as tho you may not need it, it will finish the plants in the last week or two really well. As this is a perp. grow you will need an extra grow space, perhaps a 4'x4' tent ?
Thanks for the reply! I thought 3x400w lights would be better for the coverage (electricity bill as well lol). I will google some more on coverage/example grows in the light range/etc. I do have a 4x4 tent as well I plan to use that for my veg, probably with my LED light. It will keep temps down and I can keep it close to the plant without it being hot. It would be seed (or clones) in veg for about 4-6 weeks depending on how the flowering tent is doing. In the 4x8 flowering tent it would just be 3 plants per side, one starting flowering and one finishing.