Testing Troubles…Again

[Zac]

Hey all,

I made a post about this a while ago but I seem to still be having troubles with co-op test strips vs api liquid test for nitrates. Attached are photos below. Co-op reads 25 and API reads…160? I mean I’m no expert but something doesn’t seem right.

I don’t see any stress among my guppies. They are swimming a bit fast and erratically but it could be cuz I fed them a bit ago. I also may have seen a flash but I can’t say for sure because it was out of the corner of my eye. Either way they’d be showing other symptoms if they had nitrate poisoning. They look very healthy. No signs of poisoning.  They go crazy for food and aren’t showing lethargy or anything. I did a water change as well not too long ago just because I wanted to.

I have dose 4 ml of easy green every 3 days in my 30 gallon which is barely above the advised amount. Pobably a quarter of my tank is taken up by pogo and another large amount by pearl weed (picture below). Both as you know are very fast growing. I also have other slow growing plants. One of my anubias has yellow spots on it which may be because of nitrate deficiency. The plants are doing amazing so I have to think there’s no way they’re letting nitrates get that high. If nitrates were too high the plants would have a shock I would think.

I’m extremely confused and don’t know what my course of action should be. I did notice that when I left a co-op test strip for longer than a minute it became darker and darker but I don’t think that would be accurate because the instructions say to leave it for a minute. The picture was taken around the minute mark. I do use my api tubes to distribute fertilizer because the pump isn’t working that well. I guesstimate roughly 4ml. I rinse them throughly but I suppose it’s possible some fertilizer lingered in there. The tube was dry when I tested.

Any comments or thoughts are welcome 

Edited August 3, 2022 by Zac

[SugarBassJoe]

I have the same issues with coop strips vs api liquid tests, the strips seem to read normal, but the liquid tests are always off the charts, the only thing i could think of is contamination from the tap water i used to rinse the vials out, but there shouldn't be nitrates in it, high dose aren't good for people either. i hope some one has the answer for you, because i would really like to know too.

[Katherine]

How long have you been using the current API test bottles? I found mine skewed toward higher and higher results as time went on even before expiring. It didn't matter how much I shook the darn things either. I'd trust the strips in this instance.

Edited August 3, 2022 by Katherine
Spelling

[Zac]

On 8/3/2022 at 6:38 PM, Katherine said:

How long have you been using the current API test bottles? I found mine skewed toward higher and higher results as time went on even before expiring. It didn't matter how much I shook the darn things either. I'd trust the strips in this instance.

Good point. I’ve had it for just under a year

[John Henry]

If you want to use your API tubes to measure out liquid fertilizer,  pick one tube and mark it with a Sharpie; make it your dedicated fertilizer tube and keep your other tubes clean for testing.

[Seattle_Aquarist]

On 8/3/2022 at 3:24 PM, Zac said:

Hey all,

I made a post about this a while ago but I seem to still be having troubles with co-op test strips vs api liquid test for nitrates. Attached are photos below. Co-op reads 25 and API reads…160? I mean I’m no expert but something doesn’t seem right.

I don’t see any stress among my guppies. They are swimming a bit fast and erratically but it could be cuz I fed them a bit ago. I also may have seen a flash but I can’t say for sure because it was out of the corner of my eye. Either way they’d be showing other symptoms if they had nitrate poisoning. They look very healthy. No signs of poisoning.  They go crazy for food and aren’t showing lethargy or anything. I did a water change as well not too long ago just because I wanted to.

I have dose 4 ml of easy green every 3 days in my 30 gallon which is barely above the advised amount. Pobably a quarter of my tank is taken up by pogo and another large amount by pearl weed (picture below). Both as you know are very fast growing. I also have other slow growing plants. One of my anubias has yellow spots on it which may be because of nitrate deficiency. The plants are doing amazing so I have to think there’s no way they’re letting nitrates get that high. If nitrates were too high the plants would have a shock I would think.

I’m extremely confused and don’t know what my course of action should be. I did notice that when I left a co-op test strip for longer than a minute it became darker and darker but I don’t think that would be accurate because the instructions say to leave it for a minute. The picture was taken around the minute mark. I do use my api tubes to distribute fertilizer because the pump isn’t working that well. I guesstimate roughly 4ml. I rinse them throughly but I suppose it’s possible some fertilizer lingered in there. The tube was dry when I tested.

Any comments or thoughts are welcome

Hi @Zac

I hate it when I get conflicting readings when doing tests.  I've used various test strips and API test kits over the decades I have been in the hobby.  I've found the test kits are typically much more accurate than test strips.  How can I say that?  What I did was mix up some 'calibration solutions' using distilled water an a measured amount of grams of a fertilizer salt (like potassium nitrate) which results in a known amount of ppm in the solution.  Then I use a test kit to determine if the test results match the known amount of ppm.  I do this within a range that is appropriate for my tank for example I will mix up an 80 ppm solution and test.  Then I will 'cut' that solution with an equal amount of distilled water which gives me a solution of 40 ppm and test.  Then I cut the 40 ppm solution with an equal amount of distilled water and test again to see if the test registers 20 ppm.  I found API test kits to be very accurate when the tube color is read against a white background. 

Whenever I get a new test kit I do the above before trusting the results.  Hope this helps! -Roy

[nabokovfan87]

I ran it through the colorblind tool just to try get it clear on what the real value would be for the two tests

On 8/3/2022 at 3:34 PM, Joey1991 said:

I have the same issues with coop strips vs api liquid tests, the strips seem to read normal, but the liquid tests are always off the charts, the only thing i could think of is contamination from the tap water i used to rinse the vials out, but there shouldn't be nitrates in it, high dose aren't good for people either. i hope some one has the answer for you, because i would really like to know too.

Hit the reset button....  Essentially get some isopropyl alcohol and soak the vials and clean everything.  Let it air dry or rinse in known good water and then let it dry out.

Then try to test and make sure you don't have any issues.

The alcohol should evaporate out and this might remove any contaminants you're experiencing.

 

On 8/3/2022 at 3:24 PM, Zac said:

I’m extremely confused and don’t know what my course of action should be. I did notice that when I left a co-op test strip for longer than a minute it became darker and darker but I don’t think that would be accurate because the instructions say to leave it for a minute. The picture was taken around the minute mark. I do use my api tubes to distribute fertilizer because the pump isn’t working that well. I guesstimate roughly 4ml. I rinse them throughly but I suppose it’s possible some fertilizer lingered in there. The tube was dry when I tested.

ACO has the glass measure.  I highly recommend having those around for this use!  As for the pump, take a glass of hot / warm water and then melt the crystalized liquid.  This will clear it out and you can use a push pin or paperclip to remove any stubborn chunks.  Run water through the pumphead and you'll be good to go.  Then you can use it like normal or measure as you see fit.

[Zac]

On 8/3/2022 at 8:36 PM, nabokovfan87 said:

I ran it through the colorblind tool just to try get it clear on what the real value would be for the two tests

Hit the reset button....  Essentially get some isopropyl alcohol and soak the vials and clean everything.  Let it air dry or rinse in known good water and then let it dry out.

Then try to test and make sure you don't have any issues.

The alcohol should evaporate out and this might remove any contaminants you're experiencing.

 

ACO has the glass measure.  I highly recommend having those around for this use!  As for the pump, take a glass of hot / warm water and then melt the crystalized liquid.  This will clear it out and you can use a push pin or paperclip to remove any stubborn chunks.  Run water through the pumphead and you'll be good to go.  Then you can use it like normal or measure as you see fit.

I used a different tube for the test and it read about 30-40. I think we’re in the clear but the tests still differ 

[asondhi]

On 8/3/2022 at 8:36 PM, nabokovfan87 said:

I ran it through the colorblind tool just to try get it clear on what the real value would be for the two tests. 

Sorry for the slight off-topic question. What's the tool you use? 

I'm red/green colorblind and it is near impossible for me to differentiate between the nitrate/nitrite portions of the coop strips. I've been struggling with finding strips/kits that use colors I can differentiate between easily. 

[nabokovfan87]

On 8/6/2022 at 10:41 AM, asondhi said:

I'm red/green colorblind and it is near impossible for me to differentiate between the nitrate/nitrite portions of the coop strips. I've been struggling with finding strips/kits that use colors I can differentiate between easily. 

There are some test strips you can have that will read it for you.  There is also a lot of people that will just post a photo and ask, I think everyone here is always willing to help whenever need be. I use a colorblind simulator tool that shifts the colors to different spectrums.  I have had the best success with the rightmost 2 options.

https://www.color-blindness.com/coblis-color-blindness-simulator/