Pat Kiewicz wrote

They produce more lumens of light per watt

exactly, in general the higher wattage you go the more light you get for your
money.

Metal halide lamps will produce better tseedlings for transplant than high
pressure sodium.

I disagree 100%. I understand the blue/orange light reasoning but I've used
Sodium 6 yrs straight with no
problems whatsoever. Have a look at last years seedlings.

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