Success with LED and SPS

[sphelps]

Originally Posted by chatyak

Yes, this is why I stated that it is under-rated, especially on the blue colors.

Yes and no. A typical meter will present a lower number for blue only but this number will still be relatively high in comparison to other light sources that appear brighter. The narrow peaks from LEDs in general force higher PAR numbers from a meter while not representing how much of the spectrum range used for photosynthesis is actually being filled.