Reef Central Online Community - View Single Post - Hanna Phosphorus Test Turning Navy Blue

jjencek · 09/12/2019, 07:10 AM

So I have been playing with the tester until I ran out of reagents.

Just mixing Red Sea salt in RODI does have some phosphate in it. I measured 0.073584 ppm.

But here is the weird stuff ... I tested the DT again and the blue color is nowhere to be seen. The results are back to normal - about 0.012264 ppm.

So the temporary issue is gone.

I do have one theory that I will verify when I get more reagents. I have two Hanna checkers, one for phosphates and the other one for copper. I mixed up all the vials and don't know which one I used with each tester. MAYBE the copper reagent traces react with the phosphorus reagent.

09/12/2019, 07:10 AM	#9
jjencek Registered Member Join Date: Dec 2016 Location: Prague, Czech Republic Posts: 366	So I have been playing with the tester until I ran out of reagents. Just mixing Red Sea salt in RODI does have some phosphate in it. I measured 0.073584 ppm. But here is the weird stuff ... I tested the DT again and the blue color is nowhere to be seen. The results are back to normal - about 0.012264 ppm. So the temporary issue is gone. I do have one theory that I will verify when I get more reagents. I have two Hanna checkers, one for phosphates and the other one for copper. I mixed up all the vials and don't know which one I used with each tester. MAYBE the copper reagent traces react with the phosphorus reagent.