Interesting comparisons. Though a little unfair to Kessils since it has been shown that PAR meters don't read Kessils well.
http://www.aquaillumination.com/science/par.html
http://www.aquaillumination.com/science/par.html
The 26 is actually more powerful than half of a 52. 26 is rated at 90w n the 52 at 135w.
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