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Discussion Starter · #1 ·
Since I recently started dosing pfertz nitrogen, I haven't tested my water for nitrates until now. The test is showing up very dark, I cant tell but it could be form 20 ppm to 110 ppm. I did a 25% water change earlier today and dosed with nitrogen after. Could the nitrogen dosing be messing with the test results or is the nitrogen dosing raising the nitrates?
 

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You aren't dosing nitrogen. You are dosing nitrates. The chemical element that the plants need is nitogen, but nitrogen is a gas, so it has to be "fixed" by being combined with oxygen or hydrogen before the plants can use it. Seachem "nitrogen" is actually a mix of water and a nitrate chemical, probably, but not necessarily potassium nitrate.
 

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Discussion Starter · #3 ·
I will do another 25% water change tomorrow and skip the dosing then test the nitrates. If they are still too high Ill do the same thing the next day.
 

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Discussion Starter · #4 ·
Ah well I just found a dead tetra on the ground. I'm assuming it jumped out due to the nitrates. I was dosing a pump of phertz nitrogen every day but need to get my nitrates down then start dosing every other day.
 

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I'm not sure what the groups collective wisdom is on this topic, but I would think you want to monitor Nitrate levels closely when dosing Nitrogen. In some tanks I have to dose in order to keep Nitrate levels over 5ppm, while in others I'm not dosing and having to pick up the pace with water changes each week.

Do a Nitrate test before the water change and see what it is. Do a check after the water change to see what the adjusted number is, and then do another check a week later before the next water change. That will give you an idea of what your Nitrate change is + or -. If plants are not taking up the Nitrates you don't need to dose or maybe dose as much.
 

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Your test said you had from 20 to 110 ppm of nitrate in the water. Only the very upper end of that is getting near where it could be a problem for the fish. The bigger problem is that without calibrating the test kit first, you can't tell if the readings mean anything at all. It is 50-50 that the reading from the test kit is way off.

Planted tanks need nitrates, which is why we dose them. If you just stop dosing for a couple of days the plants will consume what is in the water and bring the concentration way down. I'm assuming you have growing plants in the tank, with enough phosphates and other nutrients, plus carbon, for the plants to actually grow well.

Finding a dead tetra has nothing to do with nitrates. If you had no plants in the tank, and it was a fish only tank, it would be a different thing, but planted tanks must have nitrates or the plants just don't grow. (Blue green algae will certainly grow well though.)
 

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Discussion Starter · #7 ·
I think it was more on the 110 ppm side of things. I will calibrate my test kit tomorrow. I think the tetra jumped out of the tank due to the high nitrates. I went ahead and changed about 40% of the water and the test is now showing 0... I will run another just to be sure.

Edit: I just ran another test and it seems like it is now around 20 ppm. I will run another test tomorrow after I calibrate it.
 

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Discussion Starter · #8 ·
Hoppy, Bottomfeeder, thanks for all the help. Hoppy, does your calibrating nitrate guide with the 1/4 teaspoon of KNO3 work the same if that 1/4 teaspoon is the liquid pfertz? I'm just wondering if the concentrations are the same.
 

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Hoppy, Bottomfeeder, thanks for all the help. Hoppy, does your calibrating nitrate guide with the 1/4 teaspoon of KNO3 work the same if that 1/4 teaspoon is the liquid pfertz? I'm just wondering if the concentrations are the same.
Dry KNO3 is much, much more concentrated than any liquid fertilizer. I don't know how much Pfertz would be needed to equal 1/4 tsp of KNO3, without doing the research and calculations. Maybe someone here has already figured out the ratio between Pfertz and KNO3?
 
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