bang guy
Moderator
You hit on a sticking point with me ![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Lumens are not a measure of how much useful light a bulb has. A 175 watt 6500K MH is going to have 10X the lumens of a 175 20,000K MH. It may or may not be better for a reef.
The LOA bulb is designed to produce the brightest light for our eyes (about 557nm). The better reef bulbs avoid that spectrum entirely because it's not as useful to corals as the higher frequency light (toward the blue end, below 500nm). So, while the LOA is putting out a lot of light you need to ignore the lumen count and focus on the PAR (uh oh, another confusion item, Photosynthetically Active Radiation). A 175 MH 10,000K puts out over 3 times more PAR than the 65 watt LOA in about the same amount of space.
Lumens are not a measure of how much useful light a bulb has. A 175 watt 6500K MH is going to have 10X the lumens of a 175 20,000K MH. It may or may not be better for a reef.
The LOA bulb is designed to produce the brightest light for our eyes (about 557nm). The better reef bulbs avoid that spectrum entirely because it's not as useful to corals as the higher frequency light (toward the blue end, below 500nm). So, while the LOA is putting out a lot of light you need to ignore the lumen count and focus on the PAR (uh oh, another confusion item, Photosynthetically Active Radiation). A 175 MH 10,000K puts out over 3 times more PAR than the 65 watt LOA in about the same amount of space.