...would be to go with a nice big digital ballast, and a single thousand watt MH* for the veg, switching to a single thousand watt HPS* for the flower. If one wanted to be very non-bulb-switchy, one could buy a (kinda expensive) dual-arc bulb and get 600w HPS and 400w MH in the same bulb. Just move the hot air out.

Two 600w would be very good to fill the space, as well, and you could get a little closer to the plants. A single 600 would work, if you kept it close, and light-moved it or rotated and LST/SCRoG'ged yer plants.

If possible, try to keep yer plants under 10,000 lumens / square foot.

Just my :twocents:

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(c)C :chainsaw:

* HPS=High Pressure Sodium, MH=Metal Halide. Make sure your ballast can 'strike' the bulb of your choice, and keep the heat (and/or bugz!) off And never, ever, ever touch 'em with your bare skin, as the oils in your skin will contribute to early breakdown of the bulb.
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