Wave action affecting par readings?

[Arsenix2001]

I have 3 kessil 160we on a 39 gallon 36" long tank. Two are each side at 60% intensity and 6" above water. I have the middle light on a 45 to miss the cross brace and spot light some SPS coral in the center about 3" off water and at 80%. I have to keep it close to avoid spillover and fry nearby lps.

Played around with my new Apogee 510 and with all pumps and wavemakers on (i have alot of surface agitation) my par numbers would bounce all over the place. Id see 85- 110 on the sand bed with a ping of 125 here and there. At my SPS, right under light, it would bounce as much as 370-450.

All pumps off I got clean stable numbers avgs 100 on the sand bed and around 415 at my purple monti digitata (im either gonna roast this thing or get it to finally turn purple lol)

Is this normal with kessil? Assuming I should adjust lighting with pumps on as this is what the corals actually see?

 

[Albertan22]

I believe it’s normal with any light. The wave action defracts the light. The shimmer we see is intensified light and shadow.