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Billybeau1
10/12/2009, 11:56 AM
A little while back I found many reefers trying vodka dosing to reduce Nitrate and Phosphate levels. So I decided it was time to test nitrate test kits as this seems to be the method of gauging the effectiveness of dosing a carbon source.

I am a little disappointed at the final results of my test. But I will post them anyways and let you all draw your own conclusion.

I purchased 8 hobby grade test kits.
LaMotte
Salifert
API
Seachem
Elos
Tropic Main
Red Sea
Sera

All above tests reported results in NO<sub>3</sub>, except LaMotte. These results are in NO<sub>3</sub> - N (nitrate- nitrogen). All LaMotte results are multiplied by 4.4 to get nitrate ions.

I first tested each kit with my ro/di to make sure there was no NO<sub>3</sub> in my fresh water. No kit registered any level of nitrate in my water.

I then tested the nitrite level of my tank as elevated nitrite can skew some nitrate test kits. No kit tested higher than .02 ppm of nitrite. I believe this will be ok for our test.

Now, keep in mind, my tank has a nitrate level of over 100 (I believe). I have a Fish Only and the fish do not seem to mind much. :D

So, my first test was with a full sample of my water.

LaMotte = Over the scale. Unable to determine.
Salifert = Over the scale. Unable to determine.
API = 140 ppm
Seachem = Over the scale. Unable to determine.
Elos = Over the scale. Unable to determine.
Tropic Marin = 100 ppm
Red Sea = Unable to determine
Sera = 40 ppm

My next test was to dilute my sample 50/50 and see what it read.

LaMotte = unable to determine
Salifert = 35 ppm
API = 60 ppm
Seachem = 50 ppm
Elos = unable to determine.
Tropic Marin = 50 ppm
Red Sea = 60 ppm
Sera = 15 ppm

I then diluted the sample 10 to 1. I wanted to test each kit at the lower end of the scale since it seems most hobby grade kits are geared towards that. And since most reef tanks have much lower trates than I do.

LaMotte = 17.6 ppm - my tank - 176 ppm
Salifert = 10 ppm - my tank - 100 ppm
API = 15 ppm - my tank - 150 ppm
Seachem = 15 ppm - my tank - 150 ppm
Elos = 15 ppm - my tank - 150 ppm
Tropic Marin = 15 ppm - my tank - 150 ppm
Red Sea = 5 ppm - my tank - 50 ppm
Sera = 5 ppm - my tank - 50 ppm

General thoughts about each kit.

LAMOTTE
I love this kit. Initially a little more expensive than most but refills are not too bad. I love the color comparator. Although it read a tad higher than other kits, it is still in the ball park. Very user friendly. I give it 4 thumbs up

SALIFERT
Color chart is hard to read at low and high levels. Test is easy enough but results are inconsistent. I give it 2 thumbs up

API
This test does extremely well at high levels of nitrate but does poorly at low levels due to the color increments of the color chart. I recommend this highly for tanks with higher levels of nitrates but do not recommend it for low level testing. I give this 3 thumbs up

SEACHEM
I'm not much of a fan of many Seachem test kits but this one seemed to preform pretty well at low range testing. It is easy to use and the color chart is pretty nice with the slide indicator. It also doubles as a nitrite kit. I give this kit 3 thumbs up

ELOS
Forget this kit for high level testing (over 25 ppm) but low level it matched Saliferts. The color card is easier to read than Saliferts and the kit is easy to use. I give this kit 3 thumbs up

TROPIC MARIN
This kit actually measures high nitrates quite well. I was impressed with the kit itself as well as the instructions. Very easy to use. It also doubles as a nitrite kit. 2 for the price of one. I give this kit 4 thumbs up

RED SEA
This kit has an easy to read color chart but the results as just not consistent with the other tests. I give this kit a :thumbdown

SERA
This test kit shows the ability to test in a variety of ranges up to 400 ppm. Unfortunately, a variety of tests showed many inconsistencies in the results. I give this kit a :thumbdown

Prices vary for these test as do tests per kit.

Lamotte = $56 , refills about 20 bucks - # of tests not listed
Salifert = $20 - 60 tests
Elos = $28 - # of tests not listed
Seachem = $13 - 75 tests
Tropic Marin = $20 - # of tests not listed
API = $8 - 90 tests
Red Sea = $13 - 60 tests

Summary

I am a little disappointed as I thought the numbers would be a little more linear in the dilution stages. I guess that is why they call them "hobby grade" test kits. It does appear, however, that a number of these kits do quite well at the low levels of nitrate you are all striving for. As for an exact number, I doubt any of these kits are going to provide that.

:)

Boomer
10/12/2009, 01:04 PM
Lamotte = $56 , refills about 20 bucks - # of tests not listed

40 tests /refill

Red Sea

I played with that test when testing Lou' s Nitate meter and hated it :(

I am a little disappointed

Don't be, as testing for Nitrate and getting accurate reading can be an issue, These kits use Cadmium reduction, where NO3- is converted to NO2-. The only one we may use in this hobby better than the LaMotte is the HACK NI-14 @ 2x $ the LaMotte. I will add that the Elos kit has been tested by ENC Labs for accracy and is pretty much on.

I should have told you when we talked :( to go to HACH and get at 10 mg/ l N-NO3-( 44 ppm as NO3-) NIST std or get some of Lou's std for his Nitrate meter for seawater, 1, 10 and 100 ppm NO3-

http://www.hach.com/hc/search.product.details.invoker/PackagingCode=30749/NewLinkLabel=Nitrogen-Nitrate+Standard+Solution+as+NO3-N+(NIST),+10+mg&frasl%3BL,+Bottle&frasl%3B500+mL

tatuvaaj
10/12/2009, 01:20 PM
I'm surprised that Salifert performed so poorly, it has usually been one of the best ones in other tests:

http://www.korallenriff.de/artikel/403_Nitratmessung_im_Meerwasseraquarium_-_Teil_1.html

http://www.korallenriff.de/downloads/nitratmessung.pdf

http://www.korallenriff.de/artikel/524_Nitrat_[N03]_Wassertests_auf_dem_Prüfstand_2006.html

Boomer
10/12/2009, 01:23 PM
:lolspin::lolspin::lolspin:

I was just looking for those tat and my old link was dead so gave up on it :) You to have to reg and for that pdf one.

iFisch
10/12/2009, 03:50 PM
Billy, we appreciate your time and money put into this test. Great job. :beer:

catman78
10/12/2009, 04:03 PM
Gotta agree

Thanks Billy

Looks like I'll give the Lamotte a try. I use the Lamotte for Alk and love it.
Salifert hard to read below 10 ppm.

tegee
10/12/2009, 05:04 PM
Billy, we appreciate your time and money put into this test. Great job. :beer:

+1; outstanding post and thx for spending the time and $$$ to help us all out. I will continue to test my tank on a weekly basis with Salifert, API and Elos and try my best to post results along the way.

tatuvaaj
10/12/2009, 09:52 PM
Billy, we appreciate your time and money put into this test. Great job. :beer:
Agreed 100% ! Thank you very much!

Now that you have these kits, one interesting experiment could be to test which kit detects lowest amount of NO3. In my opinion the detection limit is more important than absolute accuracy.

Maybe try 1:1000 dilution :)

tatuvaaj
10/13/2009, 05:36 AM
And BTW, these kinds of tests would be excellent material for the Reefkeeping Magazine. They might even pay for the kits :idea:

Randy Holmes-Farley
10/13/2009, 06:20 AM
FWIW, I'm surprised they are as close as they came out. :D

ksed
10/13/2009, 06:56 AM
Good job Billy:thumbsup:

ksed
10/13/2009, 07:25 AM
Billy just curious how low on the scale does the Elos and Tropic Marin go?


Thanks

Kevin

Billybeau1
10/13/2009, 03:27 PM
Elos's color chart is 25 - 10 - 5 - 2.5 - 1 - 0

TM's is 100 - 50 - 30 - 15 - 10 - 5 - 2 - <1

luther1200
10/13/2009, 03:43 PM
I always liked my Salifert kit the best. You can look throught the side if its under 10 and it makes it much easier. But I'm sure everybody knows that. Are those other kits really that much better?

Billybeau1
10/13/2009, 04:03 PM
I don't know Matt. I could not test these kits at ultra low levels of nitrate for obvious reasons. I may have been a little hard on the Salifert. I know many use them and most have extremely low nitrate levels so it may be easier to read.

I may run one more test even diluting my sample even more. Although I am of the opinion that any tank below 10 ppm is in pretty doggone good shape. :D

I can tell you I loved LaMottes color comparator. It is pretty easy to tell the color differences on the scale. It measures as low as 1.1 ppm and goes from there 2.2, 4.4, 8.8, 17.6, 26.4, 35.2 and 44 If I had nitrates below 40 ppm, I would love this kit. I think it is worth the money. :)

And I liked the Tropic Marin because it did equally well at high levels as well as low levels.

luther1200
10/13/2009, 05:25 PM
Maybe I'll try the Lamotte next time if I have the cash ;)

MGDMIRAGE
10/14/2009, 01:25 AM
Awesome work Billy thanks!

Dejavu
10/14/2009, 04:33 AM
Great job :thumbsup:

Paco
10/14/2009, 05:16 AM
Just curious -- did you dilute with RO/DI or saltwater? Could that have made any effect?

Jeff
10/14/2009, 05:17 AM
Great Job Billy! I bookmarked this :).

Billybeau1
10/14/2009, 07:05 AM
Just curious -- did you dilute with RO/DI or saltwater? Could that have made any effect?

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
10/14/2009, 07:07 AM
Thanks all. You know I am a testing fool. :jester:






:D

Boomer
10/14/2009, 09:46 AM
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.

Billybeau1
10/14/2009, 01:41 PM
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. :)

Boomer
10/14/2009, 04:25 PM
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.

Billybeau1
10/20/2009, 12:44 PM
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. :)

tegee
10/20/2009, 01:02 PM
Great work and I like to test these readings with an electric monitor as well. Trying to get my hands on one and as soon as I do I will test them against the three kits I have. O will post as soon as possible.

Boomer
10/20/2009, 01:20 PM
Billy, put down the Playboy and get off the flippin' camode and read you PM :D

Billybeau1
10/20/2009, 01:25 PM
I already did Boomer. Message has been sent. Thanks.

Boomer
10/20/2009, 01:26 PM
Ok :)

luther1200
10/20/2009, 07:27 PM
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
10/21/2009, 03:51 PM
I was very impressed with the LaMotte. :)

tatuvaaj
10/21/2009, 11:24 PM
Billybeau1,

Thank you very much, great stuff :thumbsup:

It would be interesting to know if all kits perform as well with seawater so if you ever feel bored... :D How about 9:1 NO3-free seawater and 1 ppm standard?

Nanook
10/22/2009, 10:53 PM
Thanks for taking the time to do this study.

Billybeau1
10/22/2009, 10:58 PM
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. :)

Frogmanx82
11/02/2009, 03:27 PM
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
11/02/2009, 06:41 PM
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
11/02/2009, 07:33 PM
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?

bertoni
11/02/2009, 08:46 PM
The colorimeters won't work in seawater, for the most part. The phosphate tests should be okay, but most of the rest are not functional, including nitrate.

Billybeau1
11/02/2009, 09:19 PM
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?

Some say shake and some say swirl gently. I generally do what the instructions call for. :)

Urchinhead
11/03/2009, 09:16 AM
The colorimeters won't work in seawater, for the most part. The phosphate tests should be okay, but most of the rest are not functional, including nitrate.

Thank you sir!

tatuvaaj
11/03/2009, 10:23 PM
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.
I agree, IMO the detection limit is more important than absolute accuracy at higher levels.

ksed
11/03/2009, 10:35 PM
Tatu

Holy **** you must be up early:fun5:

tatuvaaj
11/03/2009, 11:07 PM
LOL, I have this very good alarm clock called Liida (a 2 year old girl) :D She seems to think it's important to go through 1000s of digital photos at 5:30 AM :rolleyes:

Billybeau1
11/04/2009, 12:34 AM
:lol:

Been there...... done that.......... 3 times. :D

ksed
11/04/2009, 07:03 AM
Totally understand ,2 for me.

tess&ellie
11/04/2009, 09:44 AM
Thank you so much...For a new nano tank owner the water quality is so importand i have lost 2 clown fish becayse my water levels were off I bought salifert and i guess i can't read them correctly unfortunatly two fish gave their lives for my mistake i will have great water levels before i add two more. Thanks

Plantbrain
11/04/2009, 11:52 AM
NO3 and PO4 test are notorious for inaccuracies.

I did a similar test with some test kits about 13 years ago in SF for freshwater planted systems.

Lamotte was the suggested test kit back in 1996 as a result. SeaChem at least supplied a 10ppm reference to check, but color charts are tough.

Few aquarist bother to test correctly and yet want to make all their management decisions based on unverified data from these non calibrated test kits/methods.

Testing is a PITA, no doubt, getting the aquarist to test is tough, getting to test and calibrate is 10X harder.

So if you want to make some reference solutions, just like when you calibrate a pH meter with 2 reference standards(or would you just guess with a pH meter too?).

Rather than be a nag, I'd suggest folks make their own standards and then calibrations and verify their test kits/methods. This is done for 10,000$+ lab spects for research, I see no good reason not to do it for cheapo hobby test kits.

Here's how for cheap:


Directions for Making NO3 and PO4 Reference Solutions III


You will need the following:
- 1 liter of distilled water
- 500 mL graduated cylinder
- 50 mL graduated cylinder
- 1 mL or 3 mL pipette or another measuring device to measure small mLs of solutions
- Scales that are accurate to two decimal places
- KNO3 and KH2PO4 dry fertilizers


Here's a way to make 10, 20, 30, 40 and 50 ppm NO3 reference solutions:

Add 0.70 grams of KNO3 to 429 mL of distilled. This makes a 1000 ppm NO3 solution. (It's really a 1000.72 ppm NO3 solution.)

Add 2 mL of the 1000 ppm solution to 18 mL of distilled water. This makes 20 mL of a 100 ppm KNO3 solution.

Add 15 mL of the 100 ppm solution to 15 mL of distilled water. This makes 30 mL of a 50 ppm KNO3 solution.
* Note: You can use this for the 50 ppm NO3 reference solution.

To make a 10 ppm NO3 solution:
Add 2 mL of the 50 ppm solution to 8 mL of distilled water. This makes 10 mL of a 10 ppm NO3 solution.

To make a 20 ppm NO3 solution:
Add 4 mL of the 50 ppm solution to 6 mL of distilled water. This makes 10 mL of a 20 ppm NO3 solution.

To make a 30 ppm NO3 solution:
Add 6 mL of the 50 ppm solution to 4 mL of distilled water. This makes 10 mL of a 30 ppm NO3 solution.

To make a 40 ppm NO3 solution:
Add 8 mL of the 50 ppm solution to 2 mL of distilled water. This makes 10 mL of a 40 ppm NO3 solution.



Here's a way to make 0.1, 0.2, 0.5, 1.0, 2.0, 3.0, 4.0 and 5.0 ppm PO4 reference solutions:

Add 0.70g of KH2PO4 to 489 mL of distilled water. This makes the 1000 ppm PO4 solution. (It's really a 999.04 ppm PO4 solution.)

Add 1 mL of the 1000 ppm solution to 9 mL of distilled water. This makes 10 mL of a 100 ppm PO4 solution.

Add 2 mL of the 100 ppm solution to 18 mL of distilled water. This makes 20 mL of a 10 ppm PO4 solution.

To make a 0.1 ppm PO4 solution:
Add 1 mL of the 10 ppm solution to 99 mL of distilled water. This makes 100 mL of a 0.1 ppm PO4 solution.

To make a 0.2 ppm PO4 solution:
Add 1 mL of the 10 ppm solution to 49 mL of distilled water. This makes 50 mL of a 0.2 ppm PO4 solution.

To make a 0.5 ppm PO4 solution:
Add 1 mL of the 10 ppm solution to 19 mL of distilled water. This makes 20 mL of a 0.5 ppm PO4 solution.

To make a 1.0 ppm PO4 solution:
Add 1 mL of the 10 ppm solution to 9 mL of distilled water. This makes 10 mL of a 1.0 ppm PO4 solution.

To make a 2.0 ppm PO4 solution:
Add 2 mL of the 10 ppm solution to 8 mL of distilled water. This makes 10 mL of a 2.0 ppm PO4 solution.

To make a 3.0 ppm PO4 solution:
Add 3 mL of the 10 ppm solution to 7 mL of distilled water. This makes 10 mL of a 3.0 ppm PO4 solution.

To make a 4.0 ppm PO4 solution:
Add 4 mL of the 10 ppm solution to 6 mL of distilled water. This makes 10 mL of a 4.0 ppm PO4 solution.

To make a 5.0 ppm PO4 solution:
Add 5 mL of the 10 ppm solution to 5 mL of distilled water. This makes 10 mL of a 5.0 ppm PO4 solution.

A cheap 0.01 gram scale is mighty cheap.
The KNO3 and KH2PO4 are also very cheap, see www.aquariumfertilizer.com.

Now you can check your test kit and then make a much better informed verified decision on management.

A trick to do also if you hate testing often, is to freeze small samples, say 50mls in a plastic bottle and label them with the date, then test all at once for 1 month's worth of measurements. This gives good data over time, but does not allow you to make changes day to day, or week to week, but longer term trends etc/good for testing certain hypothesis etc.

Do not take the word of this person's results and then skip this step!!!!Verify yourself for your test kit!!! Assuming their results are the same as your test kit is no good!!!! Calibration does not work that way. Each kit and hobbyists, over time, should do this if they want good results they can count on.

If you wanna guess, might not bother testing much.



Hope this helps

Regards,
Tom Barr

steve9
11/04/2009, 01:46 PM
dont sell the seachem low range nitrate kit short it comes with a reference sample and is very cheap and easy to use.
MY NITRATES ARE IN THE .9 TO .5 RANGE AND THIS THING ROCKS IN THAT RANGE and for anything up to its reference sample level to 10 its the best.........period

YOU can get the samples they use for the nitrate meter to check your test if you dont use seachem.

Awt and seachem test were always the same have tested them together 10 times.

Billybeau1
11/04/2009, 02:10 PM
FWIW, AWT's testing is suspect. As is the Seachem nitrate kit from my testing.

The LaMotte appeared to perform the best for accuracy and ease of use.

I don't put much stock in reference samples supplied with hobby grade test kits. It is too easy to match the sample to the kit no matter what it is reading.

hatemeyet
11/04/2009, 05:44 PM
Next up, I may tackle testing an electronic nitrate monitor. Stay tuned.


Do you know which one you'll be testing?Was gonna order the hanna nitrate meter but heard it wasn't accurate.But I'll wait for your test.

Great job:thumbsup:

EleganceMan
11/04/2009, 08:50 PM
Some say shake and some say swirl gently. I generally do what the instructions call for. :)

I am not talking about the test tube.....what i mean is the dropper bottles...some test kits say to shake the bottle before adding the drops and others dont but i have always shook them anyway.

Plantbrain
11/04/2009, 10:43 PM
FWIW, AWT's testing is suspect. As is the Seachem nitrate kit from my testing.

The LaMotte appeared to perform the best for accuracy and ease of use.

I don't put much stock in reference samples supplied with hobby grade test kits. It is too easy to match the sample to the kit no matter what it is reading.

I do not either, however, I also use at least 2 standards over the suspected range of the test, Lamottes are the only test kit I have suggested for hobbyists for what? 14 years now for NO3.

That's why you folks should make your own reference samples and not rely on other folks for making and doing all the work, this(not calibrating the test kits/methods) is a much more larger problem in the hobby.

If you are honest and will not ever really make a standard reference solution, then get a Lamotte NO3 test kit.

If you are serious about testing, then do yourself a favor and use reference standards. There's no 1/2 half fudging on this, you either verify or you "guess". Once you do it a couple of times, it becomes "old hat", just like the first time you goaded yourself into actually testing NO3, seemed a bit new and intimidating.

You'll get over it and then know what the measurement is(or is not).

If you have a 0.001 accurate scale, then you get another sig figure, or you can make 1 liter of reference or 10 liters worth and sell it to local hobbyists and get another sig figure by using 10X(1 sig figure) or 100X more volume(2 sig figs), but what to do with 100 liters of 100ppm NO3 solution?:clown:

You can also do this without a scale using a dosing cal and teaspoon measurements: a non chemist method:


Calibrating a test kit means using that kit to measure some water samples with known concentrations of the substance being tested for, and using those test results to verify that the test kit is accurate, or to train yourself to recognize the colors that correspond to the concentrations you want to test for. Hobby test kits are not laboratory quality tests. That means we don’t need extreme accuracy in the standard test solutions we use for calibration. If we have a good quality gram scale, with +/-.01 gram accuracy, and good laboratory glass graduated cylinders to measure water volume, there are other articles that tell how to make very accurate standard solutions. The methods described here are for use with ordinary kitchen measuring equipment, measuring spoons and cups. And, a simple dosing calculator was used to easily calculate how to mix these.

Nitrate Test Kits

First, buy a gallon of distilled water from your local grocery store. Use that to make the test standard solutions.

1. Add 1/4 teaspoon - a level measure, not a heaping measure - of KNO3 to 4 cups of distilled water (one quart). This gives you 4 cups of 800 ppm nitrate water.
2. Mix 1/4 cup of that 800 ppm water with 1 3/4 cups of distilled water. This gives you 2 cups of 100 ppm nitrate standard water.
3. Mix one cup of that 100 ppm water with one cup of distilled water. This gives you 2 cups of 50 ppm nitrate standard water.
4. Mix one cup of that 50 ppm water with one cup of distilled water. This gives you 2 cups of 25 ppm nitrate standard water.
5. Mix 1/2 cup of that 25 ppm water with 3/4 cup of distilled water. This gives you 1 1/4 cups of 10 ppm nitrate standard water.
6. Mix 1/4 cup of 25 ppm water with 1 cup of distilled water. This gives you 1 1/4 cups of 5 ppm nitrate standard water.
7. Use your test kit to measure the nitrate concentration in each of the 5,10,25, and 50 ppm nitrate standards. If you wish, add the 100 ppm standard to that set.
8. Compare the colors of those to the color card for your kit, and either verify the accuracy of the kit, or use those colors to train yourself to recognize the colors.

Your nitrate test kit is now calibrated. You can store the standard solutions in tightly sealed bottles for an indefinite period of time for future calibrations. Ideally, you calibrate the kit each time you use it.

Phosphate Test Kits

First, buy a gallon of distilled water from your local grocery store. Use that to make the test standard solutions.

1. Add 1/4 teaspoon - a level measure, not a heaping measure - of KH2PO4 to 4 cups of distilled water (one quart). This gives you 4 cups of 1000 ppm phosphate water.
2. Mix 1/4 cup of that 1000 ppm water with 2 1/4 cups of distilled water. This gives you 2 1/2 cups of 100 ppm phosphate standard water.
3. Mix one cup of that 100 ppm water with one cup of distilled water. This gives you 2 cups of 50 ppm phosphate standard water.
4. Mix one cup of that 50 ppm water with one cup of distilled water. This gives you 2 cups of 25 ppm phosphate standard water.
5. Mix 1/2 cup of that 25 ppm water with 3/4 cup of distilled water. This gives you 1 1/4 cups of 10 ppm phosphate standard water.
6. Mix 1/4 cup of 25 ppm water with 1 cup of distilled water. This gives you 1 1/4 cups of 5 ppm phosphate standard water.
7. Mix 1/4 cup of 5 ppm water with 1 cup of distilled water. This gives you 1 1/4 cups of 1 ppm phosphate standard water.
8. Use your test kit to measure the phosphate concentration in each of the 1,5,10, and 25 ppm phosphate standards. If you wish, add the 50 ppm standard to that set.
9. Compare the colors of those to the color card for your kit, and either verify the accuracy of the kit, or use those colors to train yourself to recognize the colors.

Your phosphate test kit is now calibrated. You can store the standard solutions in tightly sealed bottles for an indefinite period of time for future calibrations. Ideally, you calibrate the kit each time you use it.

This can be done for other parameters also like Alk and copper or whatever you wish.

Spoon feeding folks:p

Regards,
Tom Barr

Boomer
11/04/2009, 11:32 PM
Hi Tom you old terd are you lost :wavehand: And welcome to the Reef Chem Forum :D

Nice post but gee guy couldn't you have done that Cup stuff in ml at least :)



For those of you that don't know Tom, he is the FW planted aquarium guru that is always playing with chemicals.


The Tom Barr Report
http://www.barrreport.com/

tegee
11/05/2009, 06:13 AM
Dumb question; where can you buy KN03 and/or obtain it? Thx and GREAT info to calibrate your test kit.

Boomer
11/05/2009, 10:20 AM
KNO3 is Saltpeter and can be found in lots of places. It is very comnon as a fertilizer and used in pyrotechnics and can be found at drug stores/ local pharmacy

http://secure.sciencecompany.com/Potassium-Nitrate-500g-P16377C670.aspx

tegee
11/05/2009, 01:42 PM
Thx Boomer.......

Boomer
11/05/2009, 03:01 PM
You Bet :)

Peter Eichler
11/06/2009, 01:30 AM
For me this confirms, again, that API kits are about as good or better than most hobby grade kits. They're easy to use, accurate enough for most of our needs, and best of all they're very reasonable in price. This coming from someone that used only Lamotte for years and then later Salifert. I've been suggesting API for several things for a few years now and continue to be impressed with their value. Thanks for the testing!

tegee
11/06/2009, 05:21 AM
Agreed......+1

recife111
11/06/2009, 05:23 AM
Machery-Nagel/Tunze Test Kits are pretty good test kits, not many hobbyist are aware of them, they are expensive,

steve9
11/06/2009, 06:41 AM
I TAKE PINPOINTS nitrate cal solutions 1ppm and 10ppm and cut the 1ppm down to .5 and have tested a number of reefers in my club with seachems test and awt and for nitrates 5ppm and under seachem and awt are right on............so what am i soppose to take from this but that seachem is one great test in the low randge and super cheap to boot.......how can pinpoints nitrate cal solution not be accurate.How can both awt and seachem come back the same with 6 different tanks.

Billybeau1
11/06/2009, 08:43 AM
Oh boy........ steve, I have answers to your questions but I need a few weeks to finish my testing. I want to make sure my facts are straight before posting. When I get my testing concluded, you will have answers to your questions, I'm sure. I've spent a lot of time on this project. :)

I can tell you now that I do not care for AWT's testing methods and I certainly am not impressed with the Seachem nitrate test kit, for a number of reasons.

I will state my case soon.

Boomer
11/06/2009, 10:49 AM
Steve

I stand behind Billy. There is something going on here that nobody knows about but us and it is going to require some time with more testing. When it is done Billy will give the reasons and why. I can tell by just reading your post you have a big error there in the way you are testing. Billy knows what I mean.

Frogmanx82
11/06/2009, 09:36 PM
So where does the 5 in 1 test strip rank in all this. It couldn't be any easier and seems to show some color change at fairly low nitrate levels. Of all the parameters on the test strip, the only one I look at is the nitrate. It seems to me to be quite sufficient for detecting nitrate issues.

Billybeau1
11/07/2009, 12:09 AM
I've never tested strips. I can't imagine they can be very accurate but who knows. :)

steve9
11/07/2009, 12:35 AM
When i stopped dosing volka My nitrates jumped up to 2 for a while i tested my 2ppm reading i got from seachems test with awt and most of the kits you talk about here[except lamottes] and they all picked up some nitrates.
2 MONTHS LATER my nitrates dropped back under 1ppm awt [.6] seachem around this and all the others showed no nitrates.


Help me understand what you guys are trying to say because i dont care if my nitrates are 1ppm or .5 ppm this is accurate enough for me.
For nitrates around 1ppm this test and awt is fine to me.

The difference between 20ppm and 40ppm would concern me but this test and awt picked up my increase in nitrates and then picked up my decrease so explain youR point please.

I RESPECT your opinions very much so can YOU fill me in and i mean for testing around 1ppm..........thanks guys

Frogmanx82
11/07/2009, 08:26 AM
I've never tested strips. I can't imagine they can be very accurate but who knows. :)

I think you would be surprised how well they work for nitrate. You can certainly tell if you have 10 ppm or more. If I have no color change on the strip, I know I'm in good shape.

Boomer
11/07/2009, 12:17 PM
Steve

I'll give you this for now OK. First there are different ways for testing Nitrate, ISE probes, Photometer and test kits. Probes and spectrophometers are sensitive to salinity and must be calibrated using seawater nitrate stds. Meaning, FW stds do not work right. If you do not use the proper std they will be off. Test kits can be the same buy not by as much. Some use FW stds for kits or meters/probes for seawater and some do not. Nitrate can be expressed two different ways, i.e., N-NO3 or NO3-. 1 ppm N-NO3 does not equal 1 ppm NO3-. Some kits meters etc, may be getting calibrated or ref to with a FW Std as N-NO3 std but the kit meter is expressing the Nitrate as NO3- and not N-NO3. Some maybe cal ref to a seawater std for N-NO3 and expressing it as NO3-. And on and on. You can see what kind of mess this can led to. Many kits, meters are affected this way, but some are not, it depends on what ion you are testing for. Some tests are subject to what is called the "salt effect" error.

A good example is pH. All meters are affected by the salt error and so are many test kits. This is often the case when comparing test kits from one to another or against a meter. You ask yourself the question why is one 8.00 pH and the other 8.3 pH. Well, one is correcting and one is not. And then there is the other issue. We and most books and articles do not correct for pH. You only see corrections in advanced books or articles on pH. So, for us and almost all others, even in other fields, it is not a concern. But that kit or meter that we may be using, if it is corrected, is a concern and we need to know. So, the end of the store is in pH measurement we are more or less all on the same page but not for such things as Nitrate. I feel AWT, that uses a spectro or meter and Seachem using a kit, are in fault and others are not and why you are getting the readings you are. We are trying to see what is what here.



Fox

I think you would be surprised how well they work for nitrate. You can certainly tell if you have 10 ppm or more

I would only be surprised if this test strip was tested against a seawater ref std of 10 ppm NO3- Nitrate Ion :) And how is that test strip expressing Nitrate, as N-NO3 or NO3 ?

Frogmanx82
11/07/2009, 04:07 PM
Boomer, I think you are too hung up on the absolute number. For the most part people are just looking for changes. It doesn't matter if my bathroom scale if off 5 pounds as long as I use that scale all the time. The absolute accuracy is less important than understanding what is changing.

The problem comes of course when your comparing different scales and trying to know what the set point should be on your test method. For pH this is a larger issue than nitrate. We know the nitrate target is 0.

Billybeau1
11/07/2009, 04:22 PM
We know the nitrate target is 0.

Not necessarily. I've actually seen some reefers trying to add nitrate to accomplish a balance in their reefs. This can get complicated. :)

Boomer
11/07/2009, 09:06 PM
Frog

Not really so for some :)

I should have added this

1 ppm N-NO3 = 4.4 ppm NO3


So, if you have a meter or kit that reads 5 ppm N-NO3 it is really 22 ppm NO3-. And as you can see that is allot. And if you cal that NO3 meter say with N-NO3 std it will be a mess. A SeaTest Kit and a LaMottt, measure it as N-NO3 for example and if they read 1 it is really ~ 4.5. Are you happy with that ? For a while, till I got after Deltec, they were selling Phosphate kits that tested really low. All where running out to buy it, as they testd much lower than others. Till, I pointed out, it was not measuring PO4 but P-PO4. 1 ppm P-PO4 = ~ 3 ppm PO4. Now, they have noted that in their instructions. I'm not looking to be exact Frog it is being way off :)

2thdeekay
11/07/2009, 09:18 PM
For a while, till I got after Deltec, they were selling Phosphate kits that tested really low. All where running out to buy it, as they testd much lower than others. Till, I pointed out, it was not measuring PO4 but P-PO4. 1 ppm P-PO4 = ~ 3 ppm PO4. Now, they have noted that in their instructions. I'm not looking to be exact Frog it is being way off :)

Boomer, I was wondering about that. When did this change come about? Thanks!

Boomer
11/07/2009, 09:24 PM
More than a year ago kay

Frogmanx82
11/07/2009, 11:48 PM
Boomer, I appreciate your efforts in helping people understand what they're testing. Also important is for people to understand why they are testing and what they are going to do with the test results.

steve9
11/08/2009, 03:59 AM
I USED THE REFERENCE SAMPLE that comes with the seachem kit with other members kits[most of what you tested] and they were all around 10ppm as best you can read these things so i think you guys are splitting hairs.

for our hobby these kits work good and they are cheap......my favorite is still the seachem.
If my nitrates are really 4ppm and not .6 who cares as long as i can spot a change for the worst......MY 2 CENTS:eek1:

emoore
11/08/2009, 07:00 AM
I USED THE REFERENCE SAMPLE that comes with the seachem kit with other members kits[most of what you tested] and they were all around 10ppm as best you can read these things so i think you guys are splitting hairs.

for our hobby these kits work good and they are cheap......my favorite is still the seachem.
If my nitrates are really 4ppm and not .6 who cares as long as i can spot a change for the worst......MY 2 CENTS:eek1:

I disagree. I want to know if my nitrates are 4.4 times off. I think it is a really big deal if my test kit is reading 5 ppm but it is really 22 ppm. I have been using the Salifert nitrate kit but I think I will switch to LaMott.

2thdeekay
11/08/2009, 12:49 PM
If my nitrates are really 4ppm and not .6 who cares as long as i can spot a change for the worst......MY 2 CENTS:eek1:

:eek1: :D Steve, I'd like to politely comment that posts like that on a "reef chemistry" forum can start a fire. LOL Many folks here enjoy water chemistry more than reefing, as it's a hobby in itself. However, I do agree with you regarding not expecting too much from an inexpensive hobby kit.

That said, I'm very satisfied with the Salifert NO3 Kit. The low range seems to work just fine for reefing purposes, 0.2 - 10 mg/L as Nitrate, not N-NO3.

luther1200
11/08/2009, 01:57 PM
i disagree. I want to know if my nitrates are 4.4 times off. I think it is a really big deal if my test kit is reading 5 ppm but it is really 22 ppm. I have been using the salifert nitrate kit but i think i will switch to lamott.

+1

Boomer
11/08/2009, 11:26 PM
emoore

For low readings you may want to stick with the Sailfert, as it is NO3. The LaMotte is N-NO3 and only goes down to 0.2 N-NO3 x 4.4 = 0.88 ppm. Or this kit made for seawater


http://www.nitrate.com/sw-ntk2.htm


Ultra Low Nitrate Analysis

0.5 µM - 10µM Nitrate = 0.007 ppm - 0.14 ppm N-NO3 ( x 4.4) = 0.03 ppm - NO3- 0.62

Billybeau1
11/09/2009, 12:31 AM
0.25 to be exact. 0.25 x 4.43 = 1.1075

Either way, if your NO<sub>3</sub> is at 1 or below, you are probably in good shape. :D

Boomer
11/09/2009, 12:43 AM
Well, if you want to get picky or be exact :D

0.25 x 4.4266438 = 1.1066609

Billybeau1
11/09/2009, 12:56 AM
I should have known better. :D

Carry on my friend. :wavehand:

Boomer
11/09/2009, 12:58 AM
:love1:

Billybeau1
11/09/2009, 01:08 AM
Oh geez, now everyone is going to start rumors about us. :lmao:

emoore
11/09/2009, 06:37 AM
emoore

For low readings you may want to stick with the Sailfert, as it is NO3. The LaMotte is N-NO3 and only goes down to 0.2 N-NO3 x 4.4 = 0.88 ppm. Or this kit made for seawater


http://www.nitrate.com/sw-ntk2.htm


Ultra Low Nitrate Analysis

0.5 µM - 10µM Nitrate = 0.007 ppm - 0.14 ppm N-NO3 ( x 4.4) = 0.03 ppm - NO3- 0.62

Thanks for the tip. Have you tested the kit in your link? I am looking for a kit that is easier to read than the salifert. Maybe I will try the one in your link.

Boomer
11/09/2009, 10:18 AM
No I have not. I just found it last week, when looking for other Nitrate kits out there. :)

Billybeau1
11/10/2009, 07:38 AM
emoore, even though the LaMotte tests nitrate-nitrogen, it still does a good job at low levels and is very easy to read. Probably the easiest I've seen yet. :)

sghera64
04/09/2016, 06:10 PM
We'd all love to have a Hanna Nitrate checker. And maybe we can. Here's how:

First, use the Hanna Nitrite Low Range checker to determine the amount (if any) Nitrite in the marine sample water.

Then, what if we use the Hach NI-14 (Hach NitraVer 6 2076199) reagent (diazotization cadmium reduction) to reduce the Nitrate in our marine water to nitrite? Then we use the Hanna Nitrate Low range Checker to determine the Nitrite. If we subtract the Nitrate found in the first test, we should know the amount of Nitrate in the sample.

Boomer, what do you think?

RobbyG
04/09/2016, 07:07 PM
So which company makes an electronic Nitrate test kit for SW?

sghera64
04/09/2016, 07:32 PM
So which company makes an electronic Nitrate test kit for SW?

And does so for hobbyist prices. . . like less than $60. :facepalm:

I know Hach makes a couple of electronic colorimiters for marine nitrate, but I'm not shulling out $400 for them.

bertoni
04/10/2016, 12:11 PM
I haven't seen a cheaper meter that will do the job.