I cited a study (like, a scientific one) in an earlier post that illustrated how when higher wattage HID lights are used on a lower setting (for example, a 600 watt set at 50%, so it acts as a 300 watt) the efficiency of the light, the longevity of the light, and the spectrum of the light are all negatively effected. I am all about efficiency, but I am also all about saving money. I did some research a week ago on the subject, and the conclusion i came to was, while it would be cheaper in the long run to get the 600 and use it as a 300, it would hurt the longevity of my bulb, the efficiency of my lights, and the spectrum of light put off by the bulb.
However, if I can still get good results doing that, I am always down. Can anyone provide a link to a grow or a study that contradicts the body of research I have, to this point, been reading?
I am getting a cooltube though. They seem outstanding for my purposes.