Par meter use question

[painter1982]

I have an apogee 510 par meter. I can place the sensor on a rock next to a coral and watch it read from 200 to 450 in that spot. Bouncing the entire time. I imagine if I shut pumps off and have calm water it would smooth out. But then that’s not what the coral is actually getting. How is everyone else determining actual par at specific spots?

 

[exnisstech]

I have a 510 and don't remember it changing quite that much but its caused by the surface movement. i think it's more about the average par not an exact number. I would just shut off flow and measure or pick a number between 200 and 450 and use that.