Kelvin
I have a 72" Current Outer Orbit using 3 150 watt 14K bulbs on a 180 gallon tank. Lights are suspended 15" above the tank. Also, I have a dense cover of duckweed.
Lights are very bright, hence the duckweed.
I have grown many types of plants and have not had any issues with any of them.
I will say that the effect is different, but not unpleasant. Nice ripple effects on the water. I have mostly Cryptocoryne species and they do very well, and have even flowered on occasion.
One bad thing, is that ALL of my driftwood gets covered in a dark green brush algae. Looks nice so I don't mind. Every 7-10 days, I just use my fingers to remove excess as it does grow quickly.
Does NOT affect the plants or anywhere else, just the driftwood.
I am thinking of switching to 6500K bulbs.
On: 9:00 am
Off: 3:00 pm
On: 6:00 pm
Off: 12:00 midnight
Total Photoperiod: 12.0 hours