Par readings and when to measure

[10-snales]

OK so I have rented a Par meter from BRS my question is

1. Should I take readings with pumps off or running? I noticed when my pumps were running my par reading was all over and hard to determine reading.
2. Also Im assuming that I should take reading at my highest schedule setting Intensity?

 

[reefwiser]

Do you plan to never run the pumps?
I alway measure with the pumps running. Always test are the high intensity. Because in most cases you will be lowering the par as it will be too much.

 

[Bpb]

Problem when measuring with pumps on is the reading will jump around beyond any discernible conclusion. Holding the sensor in one place on my own tanks with the pumps on will get readings to jump around on 200+\- range which is just too much. Pumps off and still water and it’ll vary 10-20+\- which is more manageable

 

[lx_Reef]

Did you ever figure out how to get the most accurate reading ? Im on the same boat got the par meter and it jumping all around for 80 to 180 holding it in one spot