This question has probably been asked a dozen time. Here goes again :)

So,

Third grow:

Organic, soil, G-spot, 400Watt, 5 plants

They are still seedlings at this point. Under a 200watt CFL. Soon i will switch them to the MH then veg two weeks then to the HPS to flower.

Should i run both MH and HPS through the whole veg and flower. Or should i run MH two days HPS one day rotation for veg. Then opposite for Flower. I don't REALLY want to run both lights at the same time, just because of power. I am running a shit load of fans.

So to wrap i am wondering:

Veg: MH two days HPS one day, repeat
Or: MH and HPS all the time
Or: MH all the time, HPS every other or third day

Flower: HPS two days MH one day, repeat
Or: HPS and MH all the time
Or: HPS all the time, MH every other or third day.

Thoughts? Thanks in advance.

mh for grow hps flower both if you wanna in flower ..but yeah

Any other thoughts. Does it REALLY help to have both of them going.

Who is running both at the same time? Can you notice a difference?

What tku said. It really depends on the power of your MH/HPS system but providing you can keep the heat under control the more light, the better. However if you're only going to use 1 light at a time then MH for veg and HPS for flowering. No need to play around changing the bulbs all the time. Your plants will adapt to make use of the light you provide them. Happy growing.

heat isn't a problem there vented through a cool tube. And i have two lights, two ballasts. So it would all be on easy timers.

To be honest with only 5 plants, having both lights on would be excessive. Aim for around 7000 lumens/sq ft. More than that and you get a reduced growth/input efficiency.