PAR vs Surface agitation

[BZreef16]

There isn't much i could find on this subject... but I am interested to see what others think about this. How much does water agitation affect PAR values? The reason I bring this up is because my birdnest coral seems to be lacking color only in areas where the agitation is strong. (its hard to tell in photos) Also the acro under the agitation is also a bit dull. Could this be because PAR values are less caused by the movement of water.

Digitatas and other corals that are not directly under the return seem to be in great shape.

 

[Randy Holmes-Farley Verified Community Expert]

The effects are both dynamic (that is, go both up and down rapidly ) and on average likely give an overall time-averaged decrease for objects directly below the light.

https://www.sciencedirect.com/topic...waves are the cause,experimentally [140–143].

5.3.1.1 Wave Focusing and Defocussing​

Surface waves are the cause of light field perturbations in the upper sea layer. Specifically, focusing and defocusing of sunlight refracted by surface waves produce large light fluctuations whose amplitude, frequency, and depth extension have been addressed both theoretically [92,135–139] and experimentally [140–143].

 

[exnisstech]

No technical info but when I have tested par and with all pumps and such running I get par fluctuate 100-150 par. Higher fluctuation closer to the surface. I'm not sure how it affects the average par corals are receiving.