I no longer understand the different lights, how to approach mating a particular technology (PC, T5, T5HO, or MH) to different tank sizes and approaches. By sizes I mean width, breadth and depth, realizing that the spread of light from its housing, shape and efficiency of reflectors and how well it can penetrate(?) the water to depth. (Actually, I'm not sure if the way I phrased that last bit is even scientifically accurate, as why would 150W of MH light penetrate more than 150W of PC or T5/HO light?)
I do realize that the choice depends on important variables such as what one wants to accomplish: a low maintenance ("low light") tank; a high-growth, any-plant-goes, CO2-enriched tank ("high light"); or somewhere in between. I realize that tanks below some threshold in size (10 gal?) cannot use the watt-per-gallon rule of thumb as an accurate guide.
To this end I have gotten myself a PAR meter with the idea that PAR is a more "absolute" measure than watts or light type. However, I do not have access to all different light technologies, bulbs with different kelvin temperatures, reflectors, etc.
What I really would like to know, and perhaps this might be a good article subject for the Report, is how are the PC, T5, T5HO and MH technologies different from each other. What are their relative pros and cons with respect to PAR light output, heat generation, cost ("dollars per watt" or "dollars per X µmol m-2 s-1"?), longevity (how often do bulbs need to be replaced?), and that highly subjective aspect of their light quality aesthetic.
I know this is a BIG question, but I know I can't be the only one a bit lost. I think having more information about the various technologies as they apply to planted tanks would be helpful.
-Jason
I do realize that the choice depends on important variables such as what one wants to accomplish: a low maintenance ("low light") tank; a high-growth, any-plant-goes, CO2-enriched tank ("high light"); or somewhere in between. I realize that tanks below some threshold in size (10 gal?) cannot use the watt-per-gallon rule of thumb as an accurate guide.
To this end I have gotten myself a PAR meter with the idea that PAR is a more "absolute" measure than watts or light type. However, I do not have access to all different light technologies, bulbs with different kelvin temperatures, reflectors, etc.
What I really would like to know, and perhaps this might be a good article subject for the Report, is how are the PC, T5, T5HO and MH technologies different from each other. What are their relative pros and cons with respect to PAR light output, heat generation, cost ("dollars per watt" or "dollars per X µmol m-2 s-1"?), longevity (how often do bulbs need to be replaced?), and that highly subjective aspect of their light quality aesthetic.
I know this is a BIG question, but I know I can't be the only one a bit lost. I think having more information about the various technologies as they apply to planted tanks would be helpful.
-Jason