I am glad I came across this thread. Some really good info here.
When I used Radions, I had almost everything at 100%. Overall power was at 100%. My problem was that my shallow tank [8"] is 4'x2'. To get coverage I had to raise the lights up to 16" above the water. I lost a lot of par and had severe shading.
I maintain that lighting is not near as important as water quality and now I am learning more about flow.
I believe reef keepers think that lighting is an easy, magical fix; and that if we can just buy a new light it will fix all of our coral's problem.
I also think that the light manufactures know that all the buzzers and bells are what keeps people upgrading and switching brands, which equals sales.
Tanks with great coral have great water. The biggest trick is to balance the amount of nutrients in your tank with the amount of light that you are hitting it with.
I want to write more but I must get off computer now, sorry.
Yes but still, will a lower K bulb help the OP with shading and growth? I'm sticking with yes!
