Too much actinic?

the sky is blue because that is the color that is reflected back into our eyes by the upper atmosphere... but speaking of the atmosphere, did you know that there is no exact boundary between outer space and our oxygenated atmosphere

 

Yeah, the original topic of this thread is interesting, but goes against everything that I have ever read ( from credible sources of course) about light K and algal growth. Also, If you dive, you will see that the deeper you go in the water, the less algae you find. That is due to the algal need for yellow/ red light.


I recall one article I read a few years back where at a commercial marine "farm", they had a 2 vat system, interconnected, and the only variable was lighting between the 2 tanks. One was lit with a 10000k MH, and the other with a 6500k mh, both even on the same 2x250 ballast.

The 6500k tank was the only one of those 2 that ever had algal growth.

 

Every single par test that I've ever seen has shown actinics are ALWAYS lower than daylight spectrum bulbs regarding PAR values.

Surprise me!