The Chemetrics test kit requires that you get a sample of water and put it in a test vial. There is no probe-on-a-cord to make it easy and most meter's cords are too short to get very deep anyhow. I will take a long piece of 1/2" pvc pipe, hold my thumb over one end and push the other end into the pond at the depth I want to test (keeping the thumbed end above the water), then release my thumb...the pipe fills with water from that depth, put my thumb back over the end, pull the pipe out of the pond, and let it drain into a jar...then test that. This is best done from a dock or boat.

As long as you perform the test right after you take the sample the results will be fine. When I cross checked the Chemetrics against the meter, I tested water at the pond in 3 foot of water with the meter, took a sample with the pipe, walked back to the shop with the sample jar, tested with the Chemetrics and they tested equally. The time between taking the sample and testing with the Chemetrics was about 5 minutes. I'd guess that a time lapse of 10-20 minutes might make a difference (especially if your sample jar does not have a lid - I fill it to the top and lid it without any air in it), but the Chemetrics kit does not have near the resolution that a meter would and that fine of resolution is not critical for pond testing.

For example, the above test may have showed 6.2 DO on the meter, but the Chemetrics test showed somewhere between 6 and 7. Between 6 & 7 tells you what you need to know, whereas the absolute reading of "6.2" is overkill.

Fish on!,
Noel