False positives on API nitrate test?

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Mcor

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This is branching off my original thread about my insanely high nitrate readings from both tap and tank. It occurred to me to question whether the test is accurate? I'm almost at the end of my bottles for nitrate, and I'm wondering if the concentration of chemicals is higher at the end of the bottle (from maybe not shaking it up properly when it was fuller)? I'm aware it's easily possible to get false negatives if you don't shake them up properly, so can it work the other way round? The reason I'm questioning it, is that to begin with I didn't shake them up as much as I should have (a cursitory tumble before testing) and I got several 0 readings which at the time I thought was excellent since my tank is heavily planted. I used to get low readings (lightly orange) and then I learned that you needed to shake it up really thoroughly. So I started and that's when I started getting really high readings (very much in the red). I know that they are crystals in the second bottle, could they have settled and now that its almost empty and I am shaking the life out of it, whether that is the cause of the high readings. Sorry, I'm rambling, but hopefully you get what I'm asking. Thanks!
 
It's very possible. I suddenly started to get VERY high nitrate readings, so I bought a new master test kit, thinking much as you are, but got the same result. So i took a sample to my lfs, but they use api also (and got the same result, so I went out and bought another brand of nitrate test. Same result.
Turns out my nitrate had begun to spike because even though I was doing pwc twice a week, they weren't big enough. I also took out a lot of rooted plants because they were growing wild and unruly. Around that time I also removed the purigen from one of my canisters in order to medicate the tank. Any one of those things would have been manageable, but happening in a reasonably short period of time sent my nitrate off the chart.
I never knew you had to shake bottle 2 and the test tube so vigorously until I read here.
 
It's very possible. I suddenly started to get VERY high nitrate readings, so I bought a new master test kit, thinking much as you are, but got the same result. So i took a sample to my lfs, but they use api also (and got the same result, so I went out and bought another brand of nitrate test. Same result.
Turns out my nitrate had begun to spike because even though I was doing pwc twice a week, they weren't big enough. I also took out a lot of rooted plants because they were growing wild and unruly. Around that time I also removed the purigen from one of my canisters in order to medicate the tank. Any one of those things would have been manageable, but happening in a reasonably short period of time sent my nitrate off the chart.
I never knew you had to shake bottle 2 and the test tube so vigorously until I read here.

Thanks for your response. The main reason I'm questioning it is because I tested my tap water. That came out red too. It's quite possible that my tap water might have high nitrates, but its unlikely. I'll see what happens today. I'm off with a sample of both tank water and tap water to see what the LFS test results say. :)
 
Thanks for your response. The main reason I'm questioning it is because I tested my tap water. That came out red too. It's quite possible that my tap water might have high nitrates, but its unlikely. I'll see what happens today. I'm off with a sample of both tank water and tap water to see what the LFS test results say. :)

I hope it is a dodgy bottle because that's an easier fix than messing with your tap water!
 
Sounds obvious but have you checked the date on the bottle?

The test solution may have expired.

Expire 03/2017. I'll see if LFS get different results today.
 
It expires in 4 years but you're almost out?

You may be an over tester lol :p

Look forward to see the results from the store!

Ha! Yeah! I did fish-in cycling on both my tanks so lots of testing there. Oh, just thought of something else too... When I bought my test kit online, one of the bottles had leaked in transit. It was bottle 2 of the nitrates test. Plot thickens. Wish I'd put all these things together in the first place rather having mini eureka moments now. Fingers crossed it is a dodgy bottle!
 
Nitrate Levels

Hello Mc...

Not sure what you mean by an "insanely high" nitrate level. Nitrate (NO3), is at the tail end of the nitrogen cycle, so even at a pretty high level, it isn't really toxic to your fish. You can look at your fish and tell if they're stressed. They'd definitely be stressed if the water was toxic.

Most aquarium fish are adaptable to most of our public water supplies. We just need to remove the chlorine and chloramine and the water is ready for the tank.

If you're following a good water change routine, then you don't need to worry about the water properties, they'd be safe for your fish.

B
 
Ha ha ha!! New test kit in hand. LFS tested both my tap and tank and both came up ZERO!!!
 
Hello Mc...

Not sure what you mean by an "insanely high" nitrate level. Nitrate (NO3), is at the tail end of the nitrogen cycle, so even at a pretty high level, it isn't really toxic to your fish. You can look at your fish and tell if they're stressed. They'd definitely be stressed if the water was toxic.

Most aquarium fish are adaptable to most of our public water supplies. We just need to remove the chlorine and chloramine and the water is ready for the tank.

If you're following a good water change routine, then you don't need to worry about the water properties, they'd be safe for your fish.

B

You're perfectly right of course. And 'insanely high' is just how I saw it compare to how I was used to seeing it before. Fish are happy, so that's what is important.
 
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