I am buying a 600watt digital ballast that can run MH or HPS, it comes with a HPS bulb but i was wondering if i would be wasting money buying a MH for veg opposed to just running the HPS through veg and flower. Keep it real, real green
it is not necessary but i asked this question before and was told repeatedly that it will increase yields and make for nicer bud structure...although i have no experience first hand