Nitrate readings all over the place and possibly through the roof

[pandaparties]

So i ventured back into coral on my tank like 6 months ago after a crash a while back from what i think was turkey salt. Tank is 2 years old and so far most of my coral are happy. I have a couple acros browning out (though me PE is great on almost everything, acros included) so i decided to get an ATI ICP test and the results had me confused. For months i've been thinking i had phosphate issues and have been burning through GFO like crazy, well my ICP test showed it around .1, i got a salifert today showing around .04, a new Hanna ULR showing .08 while the other Hanna ive been using historically reading in around .25 - .5. I think that ones the outlier and i might have been chasing the wrong thing. My skimmer pulls out next to nothing, i have 2 algae scrubbers rated for 4 cubes each running and run socks. I feed about 1 cube of mysis and 3 silver slides a day.

My ICP test had one huge red flag, my nitrates, at like 300ppm. My hanna HR nitrate test (new reagent, new everything) is showing 7-8 and has been for months. I asked ATI to retest and they got the same result. Took it to my LFS and they ran an API and got around 40-80. I had a red sea at home that returned like 15. And then i just bought a salifert that's reading out like 150. None of the numbers seem to agree with eachother. I want my acros to retain their color and i tend to favor the ICP/Salifert accuracy but i have a hard time believing i have happy coral with nitrates of 200+. I also change about 1% water daily, have a pretty small bioload (3 large fish, 2 small fish) for my tank size (550g), and do 10% water changes weekly. I want to color my acros back up but afraid to mess with other very happy inhabitants. Anyone got any suggestions?

Ph 8.3-8.4
Calc - 505
Mag - 1410
Alk - 9

 

[Miami Reef]

Following. This will be an informative thread.

I’m not sure how I’d react. I never knew nitrate values can differ that much between all those tests. So it’s gotta be between…8ppm-400ppm? No biggie, right?

lol

 

[mbmartin06]

I Think the icp is wonky but who knows. How did you get 150 on the Salifert test? The card I have stops at 100. Are you reading the color viewing from the side?

 

[Miami Reef]

Ps. Your acros look amazing.

 

[KrisReef]

Ps. Your acros look amazing.

Agree with that, and I think you should frag them and send me the cuts so I can try and get them to grow in my balanced parameter tank.

I can’t figure out how you can get Nitrate results that far spread among the various testing methods and understanding how those results are difficult to digest. I hope someone can help solve this mystery but until they appear I’m the only one who has offered to grow a remote replacement frag to keep them alive elsewhere in case your system has a crash. I’m just that thoughtful and generous and I hope you never need my services, something else to think about and take your mind off the unexplainable parameters in your situation.

The tank looks too clean for the test results, pretty neat! HTH

 

[gbroadbridge]

So i ventured back into coral on my tank like 6 months ago after a crash a while back from what i think was turkey salt. Tank is 2 years old and so far most of my coral are happy. I have a couple acros browning out (though me PE is great on almost everything, acros included) so i decided to get an ATI ICP test and the results had me confused. For months i've been thinking i had phosphate issues and have been burning through GFO like crazy, well my ICP test showed it around .1, i got a salifert today showing around .04, a new Hanna ULR showing .08 while the other Hanna ive been using historically reading in around .25 - .5. I think that ones the outlier and i might have been chasing the wrong thing. My skimmer pulls out next to nothing, i have 2 algae scrubbers rated for 4 cubes each running and run socks. I feed about 1 cube of mysis and 3 silver slides a day.

My ICP test had one huge red flag, my nitrates, at like 300ppm. My hanna HR nitrate test (new reagent, new everything) is showing 7-8 and has been for months. I asked ATI to retest and they got the same result. Took it to my LFS and they ran an API and got around 40-80. I had a red sea at home that returned like 15. And then i just bought a salifert that's reading out like 150. None of the numbers seem to agree with eachother. I want my acros to retain their color and i tend to favor the ICP/Salifert accuracy but i have a hard time believing i have happy coral with nitrates of 200+. I also change about 1% water daily, have a pretty small bioload (3 large fish, 2 small fish) for my tank size (550g), and do 10% water changes weekly. I want to color my acros back up but afraid to mess with other very happy inhabitants. Anyone got any suggestions?

Ph 8.3-8.4
Calc - 505
Mag - 1410
Alk - 9

I suspect the whatever method ATI use to measure Nitrate is faulty or contaminated.

ICP itself cannot measure Nitrate.

 

[taricha]

My ICP test had one huge red flag, my nitrates, at like 300ppm. My hanna HR nitrate test (new reagent, new everything) is showing 7-8 and has been for months. I asked ATI to retest and they got the same result. Took it to my LFS and they ran an API and got around 40-80. I had a red sea at home that returned like 15. And then i just bought a salifert that's reading out like 150.

ATI double-checked and got Very High
API at LFS got Very High
Salifert got Very High

Hanna HR NO3 checker has been known to have sets of dud packets - that read incorrectly low.
Depending on what the NO3 test is, 15 might be on the high range if it's NO3 Pro.

I think it's high NO3.
humor us and do a NO2 (nitrite) test, just for kicks.

 

[gbroadbridge]

ATI double-checked and got Very High
API at LFS got Very High
Salifert got Very High

Hanna HR NO3 checker has been known to have sets of dud packets - that read incorrectly low.
Depending on what the NO3 test is, 15 might be on the high range if it's NO3 Pro.

I think it's high NO3.
humor us and do a NO2 (nitrite) test, just for kicks.

All good points, forgot about RS Pro NO3 even though I had one - I used to dilute.

 

[pandaparties]

I Think the icp is wonky but who knows. How did you get 150 on the Salifert test? The card I have stops at 100. Are you reading the color viewing from the side?

Not very scientific but it was over 100 so I doubled the volume and then multiplied the result by two. I think the side is for below the threshold. At the very least it was over 100

 

[pandaparties]

ATI double-checked and got Very High
API at LFS got Very High
Salifert got Very High

Hanna HR NO3 checker has been known to have sets of dud packets - that read incorrectly low.
Depending on what the NO3 test is, 15 might be on the high range if it's NO3 Pro.

I think it's high NO3.
humor us and do a NO2 (nitrite) test, just for kicks.

I'm leaning towards high too but even the spread on the high end seems pretty varied. And it wasn't the pro rest for red sea. It's also hard to believe my coral are happy in that range and I'm getting good PE

I don't have a nitrite test on hand but I'll grab one tomorrow and update everyone.

 

[mbmartin06]

Not very scientific but it was over 100 so I doubled the volume and then multiplied the result by two. I think the side is for below the threshold. At the very least it was over 100

It is, just making sure it’s not 10 I am on the side of they are high fwiw.

 

[Randy Holmes-Farley]

Can you post the ATI results?

One thing to note is that in many sorts of nitrate tests, a little nitrite can be detected as a lot of nitrate, and the degree of multiplication there varies by test kit brand.

Thus, it is possible if there is a bit of nitrite (not a concern) that all the nitrate kits will be reading as they are supposed to, and nitrate values will still be all over the map.

 

[pandaparties]

Here's the ATI, they said they did chromatography for the NO3 which shouldn't be affected by NO2 as far as i know but that would definitely explain the other tests. Thanks everyone for chiming in on this. I am going to get the nitrite done today and run a second gamut of nitrate

 

[pandaparties]

Did a nitrite test and it came up as zero. Did a second API nitrate test 0-10 range, another Hanna test showing up as 7. No water changes no dosing anything, measured at similar time of day. Going to do another salifert after I cook dinner.

All the tests were done with exact amount of liquid in rodi pre-rinsed containers. Feel like I'm losing my mind here lol

 

[pandaparties]

Salifert showed between 25 and 50 today.

 

[gbroadbridge]

Salifert showed between 25 and 50 today.

Do you have another batch of Hanna Nitrate reagents ?
As pointed out above, there have been faulty batches

 

[pandaparties]

Do you have another batch of Hanna Nitrate reagents ?
As pointed out above, there have been faulty batches

Ah I forgot to get new reagent and my lfs is closed now. I'll get another lot number tomorrow and retest, though doesn't explain the massive difference on both the API and Salifert test in a single day.

 

[Randy Holmes-Farley]

Ion chromatography should not have the same interference, assuming they do it correctly, and no kits should get less than the ATI value if ATI did it correctly.

How did you measure nitrite?

 

[pandaparties]

Ion chromatography should not have the same interference, assuming they do it correctly, and no kits should get less than the ATI value if ATI did it correctly.

How did you measure nitrite?

Did a salifert and API, both showed zero for nitrite

 

[Randy Holmes-Farley]

Ok, then I think I’d assume there is significant nitrate, but likely not as high as the icp company result.