ok mate, do u think the mh is a must for vegging or will the hps be ok for now for veg and flower? also have you grown with just a hps and how much better was it when you added the mh??
thanks
Damn, can't trust the fingers this time of day, they get heavy and confused on the keyboard.
Here's what I think I know.....if I'm completely wrong hope someone with more knowledge jumps in.
People do veg and flower with HPS alone, so it works. There's also something called a MH conversion bulb that works in an HPS ballast. You might get one of those later when you're comfortable with the hydroponic process and have extra bucks, oops..pounds.
The type of light from these bulbs is VERY different. MH is high on the blue end of the spectrum, HPS is high on the red end. Blue is better for veg, red helps them flower. Attached pictures of the same place, same camera, two different bulbs, the difference in the light is obvious. Green pic is MH, close to daylight, next is HPS. Very different light.
Overall, photoperiod is the most important factor.
Hope this helps.
P.S. Always used the two bulbs, never had the opportunity to compare.