Billybeau1
Premium Member
I diluted with ro/di and I do not believe it makes any difference. Nitrate is nitrate. And even if I diluted with a saltwater mix, I do not think it would have made much of a difference.
A test of Nitrate Test Kits
- Thread starter Billybeau1
- Start date
I diluted with ro/di and I do not believe it makes any difference. Nitrate is nitrate. And even if I diluted with a saltwater mix, I do not think it would have made much of a difference.
Billybeau1
Premium Member
Thanks all. You know I am a testing fool. :jester:
I diluted with ro/di and I do not believe it makes any difference.
This is usually the case but not always. Long ago tests where done on Copper test kits in a lab and it was found the old API was the most accurate and was found to be more accurate if freshly made seawater was used instead of RO/DI. And your 10:1 dilution is about max you want to go. Some kits like HACH or those using Nessler Tubes do not use dilution factor but just change the focal length of the sample, some using mirrors, such as the HACH. As the dilution factor increases reliability decreases. And why you may have found would be a little more linear in the dilution stages.and as you dilute you are changing the ion concentration, its TDS, which in some kits can/will cause shift in readings.
While playing yesterday at the LFS I could not believe my eyes with the API test kit, which showed 20 ppm, FasTest 35 as N-NO3- ( 154 ppm NO3). Tetra kit way beyond its 100 ppm and Lou's Nitrate meter "High" beyond its limit of 100 ppm. Back today for some more tests, as I forgot the 100 ppm NO3- std. Those API reagents must be bad.
At the LFS I tested like 12 tanks and all but 2 where way above 100 ppm. I tested 2 tanks at Jay's, who had no NO3- kit and both tanks where "Low". Meaning less than 1 ppm. Jim's 2 tanks and 2 Rubbermaid holding tubs had ranges from 35 - 85 ppm but he has just moved. So, he has not done any WC for 3-4 months and there is no filtration or sumps. Jim had a Red Sea Kit, which was just the shits. Back to his house today also.
This is usually the case but not always. Long ago tests where done on Copper test kits in a lab and it was found the old API was the most accurate and was found to be more accurate if freshly made seawater was used instead of RO/DI. And your 10:1 dilution is about max you want to go. Some kits like HACH or those using Nessler Tubes do not use dilution factor but just change the focal length of the sample, some using mirrors, such as the HACH. As the dilution factor increases reliability decreases. And why you may have found would be a little more linear in the dilution stages.and as you dilute you are changing the ion concentration, its TDS, which in some kits can/will cause shift in readings.
While playing yesterday at the LFS I could not believe my eyes with the API test kit, which showed 20 ppm, FasTest 35 as N-NO3- ( 154 ppm NO3). Tetra kit way beyond its 100 ppm and Lou's Nitrate meter "High" beyond its limit of 100 ppm. Back today for some more tests, as I forgot the 100 ppm NO3- std. Those API reagents must be bad.
At the LFS I tested like 12 tanks and all but 2 where way above 100 ppm. I tested 2 tanks at Jay's, who had no NO3- kit and both tanks where "Low". Meaning less than 1 ppm. Jim's 2 tanks and 2 Rubbermaid holding tubs had ranges from 35 - 85 ppm but he has just moved. So, he has not done any WC for 3-4 months and there is no filtration or sumps. Jim had a Red Sea Kit, which was just the shits. Back to his house today also.
Billybeau1
Premium Member
Well, if it makes you feel any better, every water sample I have ever tested from an lfs had high nitrates. I think it is the nature of the beast. Massive volumes of water usually not changed out very often and hundreds of fish pooping every day.
I'm glad you found an interest in this. I wonder what the "born on date" was of that API kit ? It is the last four digits of the lot # stamped on the bottle.
And gosh, Fastest, I haven't seen one in awhile. They, like LaMotte measure nitrate-nitrogen as opposed to just nitrate ions.
I still think I will try one more time to cut my water sample to 20-1. I'm not as interested in the final result , rather how each kit I have compares with each other at low nitrate levels.
I think I will also test the Hach standard nitrate solution to see how each kit reacts.
I'm glad you found an interest in this. I wonder what the "born on date" was of that API kit ? It is the last four digits of the lot # stamped on the bottle.
And gosh, Fastest, I haven't seen one in awhile. They, like LaMotte measure nitrate-nitrogen as opposed to just nitrate ions.
I still think I will try one more time to cut my water sample to 20-1. I'm not as interested in the final result , rather how each kit I have compares with each other at low nitrate levels.
I think I will also test the Hach standard nitrate solution to see how each kit reacts.
Well, I did not expect them to be that high at this sore as they do allot of WC and almost all of these tanks were FOT. However, from my post.... Back today for some more tests, as I forgot the 100 ppm NO3- std.
WOW !! Did that make a difference. I had the meter cal for low range 1- 10 ppm for Jay's tanks. And re-did it for 10 -100. Most of the tanks dropped by 30 ppm. Now all tanks read on Lou's meter were below 100 ppm par 1, which could only be measured with the FasTest. The API is fine. The guy at the LFS, who I had running around like squirrel, so I could play with Lou's meter, was doing test kits for me and screwed up and apologized. He said "in these API nitrate kits you really need to sake the reagent bottles first " and he did not. The API kit seemed to be right on with the meter in their reef tank @ ~ 10 ppm and also confronted to Lou's meter on other high tanks. The issue with all kits is getting the best idea where you are at, as the jumps in kits are so big in ppm, like those you posted. Lou's meter is 1 ppm all the way up to 100 ppm, i.e., 23 ppm, 25 ppm, 26 ppm. Tomorrow I'll be re-doing Jim's' tanks.
WOW !! Did that make a difference. I had the meter cal for low range 1- 10 ppm for Jay's tanks. And re-did it for 10 -100. Most of the tanks dropped by 30 ppm. Now all tanks read on Lou's meter were below 100 ppm par 1, which could only be measured with the FasTest. The API is fine.
The guy at the LFS, who I had running around like squirrel, so I could play with Lou's meter, was doing test kits for me and screwed up and apologized. He said "in these API nitrate kits you really need to sake the reagent bottles first " and he did not. The API kit seemed to be right on with the meter in their reef tank @ ~ 10 ppm and also confronted to Lou's meter on other high tanks. The issue with all kits is getting the best idea where you are at, as the jumps in kits are so big in ppm, like those you posted. Lou's meter is 1 ppm all the way up to 100 ppm, i.e., 23 ppm, 25 ppm, 26 ppm. Tomorrow I'll be re-doing Jim's' tanks.
Billybeau1
Premium Member
OK, part two of my nitrate testing is done. I took the previous 8 nitrate test kits and tested them with 2 Hach Nitrate Nitrogen Standard Solutions.
The first solution is 1,00 +/- 0,01 mg/l as N or 4,43 +/- 0,04 mg/l as NO<sub>3</sub> so each kit should read between 4 and 5 ppm.
LaMotte = 4
Salifert = 5
API = 5-10
Seachem = 3-5
Elos = 3-5
Tropic Marin = 5
Red Sea = 2.5
Sera = 2-4
All in all, most performed well at these low levels.
The second solution is 10,0 +/- 0,1 mg/l as N or 44,3 +/- 0,4 mg/l as NO<sub>3</sub> so each kit should read this around 44 to 45 ppm
LaMotte = 44 (this is the highest reading but it was right on the money)
Salifert = 25 - 50 (tough to distinguish the color chart at this level)
API = 40
Seachem = 30 - 50 (tough to distinguish the color chart at this level)
Elos = over 25 (this is the highest this kit registers)
Tropic Marin = 30 - 50 (tough to read the color chart at this level)
Red Sea = 25 - 50 (not much color difference between these two)
Sera = 20 (this kit seems to read low although, in fairness, the kit is getting close to its exp date. It may just be expired. I do like the color chart on this kit. Easy to read.
In Summary, most hobby grade nitrate kits seem to perform well enough at low levels. Only a couple seem to perform well at higher levels. API and Tropic Marin. The all around winner for me accuracy, ease of use and readability is most definitely the LaMotte. In my opinion, it is worth the initial up front cost.
Next up, I may tackle testing an electronic nitrate monitor. Stay tuned.
The first solution is 1,00 +/- 0,01 mg/l as N or 4,43 +/- 0,04 mg/l as NO<sub>3</sub> so each kit should read between 4 and 5 ppm.
LaMotte = 4
Salifert = 5
API = 5-10
Seachem = 3-5
Elos = 3-5
Tropic Marin = 5
Red Sea = 2.5
Sera = 2-4
All in all, most performed well at these low levels.
The second solution is 10,0 +/- 0,1 mg/l as N or 44,3 +/- 0,4 mg/l as NO<sub>3</sub> so each kit should read this around 44 to 45 ppm
LaMotte = 44 (this is the highest reading but it was right on the money)
Salifert = 25 - 50 (tough to distinguish the color chart at this level)
API = 40
Seachem = 30 - 50 (tough to distinguish the color chart at this level)
Elos = over 25 (this is the highest this kit registers)
Tropic Marin = 30 - 50 (tough to read the color chart at this level)
Red Sea = 25 - 50 (not much color difference between these two)
Sera = 20 (this kit seems to read low although, in fairness, the kit is getting close to its exp date. It may just be expired. I do like the color chart on this kit. Easy to read.
In Summary, most hobby grade nitrate kits seem to perform well enough at low levels. Only a couple seem to perform well at higher levels. API and Tropic Marin. The all around winner for me accuracy, ease of use and readability is most definitely the LaMotte. In my opinion, it is worth the initial up front cost.
Next up, I may tackle testing an electronic nitrate monitor. Stay tuned.
Billybeau1
Premium Member
I already did Boomer. Message has been sent. Thanks.
luther1200
Premium Member
Thanks Billy, I might have to give that LaMotte test kit a try next time. I have read that some other people were happy with them also
Billybeau1
Premium Member
I was very impressed with the LaMotte.
Billybeau1
Premium Member
I could try that although I'm not sure what it will tell us.
The test I did with the 4.43 mg/l standard solution pretty much tells the tale.
I'm not sure other than elevated nitrite, what in seawater could affect the outcome of these tests.
I'll test the electronic nitrate monitor next and we'll go from there. I'm especially interested in seeing how the electronic monitor measures low and high levels of nitrate.
Thanks Dave.
The test I did with the 4.43 mg/l standard solution pretty much tells the tale.
I'm not sure other than elevated nitrite, what in seawater could affect the outcome of these tests.
I'll test the electronic nitrate monitor next and we'll go from there. I'm especially interested in seeing how the electronic monitor measures low and high levels of nitrate.
Thanks Dave.
Frogmanx82
New member
Isn't the low levels the only important thing. Anything over 10 ppm and you can use a quick 5in1 test strip. In fact I find the test strip to be about as good as anything else for nitrate. I'm looking for no color change. If there is a hint of purple, I need to step up my nitrate control.
Urchinhead
New member
Perhaps a stupid or off topic question but... How do these kits compare to using a colorimeter like the one made by Hanna? I ask because I am on the bubble between going Salifert for low level NO3 and ponying up the $$$ for a colorimeter by Hanna...
EleganceMan
New member
Billy,
Really good info, nice job and thank you. One questions...do you only shake the testing bottles if the instructions call for it? I have always shook them even if it doesnt say too, and I am now wondering if that could be bad?
Really good info, nice job and thank you. One questions...do you only shake the testing bottles if the instructions call for it? I have always shook them even if it doesnt say too, and I am now wondering if that could be bad?
Billybeau1
Premium Member
Some say shake and some say swirl gently. I generally do what the instructions call for.
