2-165w, Viparspectra 12" above surface, 48x18x18 tank.
Running 25 months at 100% blue, 40% white.
No problems with 7 different Monti, and 3 Acros to date.
The problem with the unmixed Viparspectra type lights is the light is not as diffused which can lead to hotspots. I am fixing this problem by adding a Halo in the middle with its 110 degree lense which uses one lense to really mix those spectrums and soften the Vispar hot spots.