Mercury vapor lamps

I am using two 175-watt mercury vapor lamps, one cool white bulb and one clear. The buds are remarkable! Why don’t I see more growers using these MV lamps? My electric bill hasn’t gone up but about $20 a month.
Lubbock, Texas

There are two problems with mercury vapor lamps. First, they are not as efficient at turning power to light as HPS or MH lamps are. Using the same current, they emit less than half the light as an HPS and only 60% of an MH. Secondly, mercury vapor lamps, even with improved spectrums, emit a lower percentage of useable light than the more efficient lamps.

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