Dennerle Lighting Recommendations

I just received my copy of _System_for_a_problem-free_aquarium_, by Dennerle.  I
was somewhat disappointed when comparing it to _The_Optimum_Aquarium_ in that
Dennerle seems to be lacking in formualaes and hard data, but instead chose to
express his system in terms of how many of "part number x" for a given size tank
was required.

Nevertheless I found it interesting that the book advocates and sells Mercury
Vapor Lamps as a high intensity "point" source of lighting.  After reading most
of the archived Usenet articles on lighting on just didn't see many people
advocating the use of these lamps.

Does anyone have practical experience with these lamps?  Are they suitable for
use in a heavily planted freshwater tank?

*Mike Roberts - mike at microspan_com
*North American Internet, Ltd. - http://www.nail.net
*Colorado Springs, CO - (719) 635-NAIL

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