Does pump need to be running to take a water sample?

[Poolweekender]

I've read that it's best to have the pump running for awhile before taking a water sample, as the Fc might be lower near the surface.
However I usually take a sample after sundown from a 48 inch AGP, and take the sample from elbow depth (at last 1/3 the way down).
My pump goes off a couple of hours before sundown...do you think I need to start up the pump for 15 mins before I take this sample?
I guess I should test before and after running the pump to see if there's any difference...
Any comments appreciated ...
Thanks...

 

[Jimrahbe]

pwe,

It should not make any difference as long as you don't take a sample right after you add something you plan to measure..

Thanks,

Jim R.