artificial lights: HPS, HMH, or both?
 

I was surprised when using search engine how few threads on artificial lights there was.
I know that 'blue' light promote vegetation and 'red' promote flowering. I've been using 440w latest generation of HPS that have also a blue wavelenght for 8 months and every plant flowered.
However, vegetative growth looks very slow to me. I have a phal monoculture about 30 plants with light candles ranging from 1300 to 800 depending on placement on a 4x4 feet growing area.
My question is: would it be more efficient for all around growing/flowering to alternate from HPS to MH monthly? I know it would mean 2 differtent ballasts. Any expert on artificial light out there to answer?

I am by no means an expert so hopefully some of the members of the board can chime in and give you some advice, but having grown before under HPS and MH, I have had much better results using T5 High Output, as you can achieve a better overall spectrum of colour to accomodate both veg and flowering.