So I read this interesting article a few weeks about how blue light is (or can be) harmful to your health:
https://www.health.harvard.edu/stayi...as-a-dark-side
It just occurred to me that this might be an interesting topic for discussion. I know that pretty much everyone is running some form of blue light on their tanks, even at night time (evening) hours. My 22K T5s used to to run all the way to 10pm so that I could enjoy my tank. I've since reduced that by an hour and now cut them off at 9pm.