Uuuuuhhhhhhhhhhhhhhhh .... no. I did not come anywhere close to saying anything of the sort.
The question began; "
I tried to grow a couple of times without much success mainly cause i was trying things gheto style. Going to change that this attempt an do things right."
Well, if he wants to; "do things right" than my answer was self explanatory.
CMH is a broad spectrum bulb. They put off a lot of light spectrum/wavelength that plants don't use and or hardly use. That is not beneficial for plants. Didnt mean to put words in your mouth.
If you want good lighting purchase a HID that will allow you to use a MH (6500K) bulb for vegging and a HPS for flowering.
Look at the light spectrum put out by a CMH bulb (in double graph with HPS spectrum also). Then look at the graphs that shows what wavelengths/spectrum that Chlorophyll A uses, one is a still graph and the other a GIF.
The greenish line on the GIF shows the rate of photosynthesis. There are two high points. The one to the left is plants in veg and the one to the right is plants in flower. They show how much of each wavelength/spectrum plants use during different stages of growth.
The black line shows the absorbance of Chlorophyll A. The high point, the spike to the left side (of both the still and moving graphs) are plants in veg and the high point, the spike to the right are plants in flower.
A 6500K MH bulb best matched the peak in veg without creating large amounts of hardly used, or totally unused light, such as a CMH creates. A HPS does the same thing for when plants are in flower.
A bulb of any wattage will only put out 'X' amount of light. Now what makes more sense, to use bulbs that only put out the wavelength/spectrum that plants need and will use the most while in either veg or flower, dedicating their entire light output to the greatest need plants have during each phase of growth, or use a bulb that creates less of each wavelength/spectrum plants need during each phase of growth, but it creates large amounts of wavelength/spectrum that plants either do not need or do not use, much of it at any stage of growth, let alone during each specific stage of either veg or flower?
If the question was, I want to use one type of bulb and only one type of bulb from start to finish, so what should I use? I would suggest a CMH.
But that was not the question. It was between CHM and HPS, but without any thought about MH and the combination of MH for veg and HPS for flower.
Since it was said that he wants; "to do things right," suggesting a third, and far better option, was only logical.
View attachment 2034276View attachment 2034275View attachment 2034277