I’m doseing phosphates and nitrates seam connected?

[Backreefing]

I’m doseing phosphate at the thread title says. And I’m noticing that as phosphate goes up so does nitrates. And as phosphate goes down so does my aquariums nitrates.
Anybody know what is with this ? Currently as of today, phosphate is 091 ppb and nitrates are 20ppm Testing done with Hanna ulr phosphate tester , and API nitrate tester.

 

[Dan_P]

I’m doseing phosphate at the thread title says. And I’m noticing that as phosphate goes up so does nitrates. And as phosphate goes down so does my aquariums nitrates.
Anybody know what is with this ? Currently as of today, phosphate is 091 ppb and nitrates are 20ppm Testing done with Hanna ulr phosphate tester , and API nitrate tester.

The PO4 measurements are more trustworthy than the nitrate measurements. API is trustworthy but was designed to be a quick test and cover a broad range. Even at 20 ppm, the color is quite saturated and subject to large variation in interpretation. If you like the API test, dilute thr aquarium sample so that the color intensity is in the 0 - 10 ppm range. Even if you decide to purchase another kit, you will still need to dilute the sample. The human eye has difficulty in perceiving differences in color intensity at high color saturation levels.

When the nitrate measurements are tightened up, I think the current trend will disappear.

 

[Randy Holmes-Farley]

They will often be used together (coral and algae uptake), and can also be added together (as in fish waste), but dosing phosphate is not going to increase nitrate, and dosing nitrate is not going to increase phosphate.