Here Is A Way To Measure Ammonia Accurately

Dan_P

Valuable Member
View Badges
Joined
Sep 21, 2018
Messages
2,043
Reaction score
1,909
In my frequent conversations with @brandon429, ammonia measurement is a frequent topic. It seems that our colorimetric hobby kits are difficult to interpret at the low end of the scale. Many users have trouble deciding whether the test is indicating 0 ppm or 0.25 ppm. In turn, this can lead them to conclude that the nitrogen cycle has stalled in their new aquarium or that their established system had an ammonia spike. Even though we can easily argue that these events are false positives, having an unambiguous ammonia reading would be best.

Some time ago @taricha and I needed to measure low concentrations of ammonia. We ended up optimizing the much maligned API ammonia test kit. We were able with the aid of either a spectrometer or Hanna Checker to measure total ammonia levels below 0.1 ppm and detect the presence of ammonia at ~0.05 ppm. I applied similar adjustments to the Red Sea ammonia test kit and achieved similar results. In addition, I developed standard curves for several popular Hanna Checkers (LR PO4, ULR P, and Alkalinity Checkers) to measure the color intensity of the modified Red Sea test.

The New Red Sea Recipe

I did the development work on 5 mL samples. You will need to double the recipe to make enough solution for a Hanna Checker. For 5 mL of sample, add 0.05 mL (Salifert red scoop) of the powder reagent A (for a 10 mL sample, one level white scoop, 0.15 mL, supplied with the Red Sea should be OK). When it is completely dissolved add two (2) drops reagent C, swirl to completely dissolve, and then add two (2) drops reagent B, one at a time and swirling the solution to dissolve the drop. The “add drop-swirl” seems to minimize yellow color formation. Let the test color develop for one hour. Here is a picture of my standard curve test solutions. Notice how nearly colorless the “zero” sample is all the way to the right. 0.05 ppm is next to it. Cool right?

29252DFC-A1BA-49D5-8E10-34200BFAD22F.jpeg


Hanna Checker Standard Curves

I found three Hanna Checkers to be useful for measuring the color intensity of the modified Red Sea ammonia test.

HI 713, LR PO4 Checker Standard Curve

E04B2F5D-FAE1-45F8-915B-73AF96CF5EEC.png


The curve is not exactly linear, probably because the wavelength of light used in this Checker does not correspond to the peak absorbance of the test color. It is measuring the far edge of the peak. For our purposes, the linearity is sufficient.

Another feature to note are the two data points that touch each other. This is a problem with the test chemistry and limits how small of a concentration can be measured with this method. I estimate that the method can be trusted for a ammonia quantity to just below 0.1 ppm. The good news is that this method can detect total ammonia down to at least 0.05 ppm. This means the solution will color up at 0.05 ppm NH3 but we cannot assign a value. The picture below demonstrates the difference in color between 0 (on the right) and 0.05 ppm.

A6CCA98E-E679-4F52-90A3-02303B8DFE87.jpeg



HI 736, ULR P Checker Standard Curve

0414922F-37EA-4EBB-8AD9-868AAB044457.png


In this curve you can more easily see how the standard curve drops off after 0.1 ppm. Again, we can measure down to 0.1 ppm but we can detect down to at least 0.05 ppm.

HI 755, Alkalinity Checker Standard Curve

29993C87-9264-4CB7-9D42-BF584C35D14F.png


Because of the way this Checker is programmed, it calls solutions with a color intensity of the 0.2 ppm NH3 test solution “zero”. This Checker might be useful in a pinch though.

Here is my standard curve data.

976BD01E-1AB4-41DC-914B-98F72FD7BF6E.png
 
https://www.youtube.com/c/ReefStache

Doctorgori

Valuable Member
View Badges
Joined
Mar 18, 2019
Messages
1,938
Reaction score
1,972
Location
NE Ohio
I’m gonna say if true: Groundbreaking ! and kudos ...
I’m going back in for a re-read

edit add: Dang, wish you had saved the API test kit translations, Red Sea prices ..yuck! :p
Thanks for doing this!
 

brandon429

why did you put a reef in that
View Badges
Joined
Dec 9, 2014
Messages
18,570
Reaction score
15,261
Location
tejas
When we can get a few measures of this ran on active reef tanks that will be really breakthrough patterning to study cycle dynamics

wow chemistry here

just read above where the Hanna checkers were used thats really nice work Dan I bet a lot of people find this very creative and effective for meeting needs for nh3 determination
 

taricha

2500 Club Member
View Badges
Joined
May 22, 2016
Messages
3,183
Reaction score
4,181
Here is a picture of my standard curve test solutions. Notice how nearly colorless the “zero” sample is all the way to the right. 0.05 ppm is next to it. Cool right?

29252DFC-A1BA-49D5-8E10-34200BFAD22F.jpeg


Hanna Checker Standard Curves

I found three Hanna Checkers to be useful for measuring the color intensity of the modified Red Sea ammonia test.
So using that pic as an approximate color card....
right to left:
0
0.05
0.1
0.2
....
etc. is the leftmost 3.2? can you fill in the blanks?

Also, anyone who has the hanna Low Range Si checker, it's prefect for this application (though a bit less common).
 
OP
Dan_P

Dan_P

Valuable Member
View Badges
Joined
Sep 21, 2018
Messages
2,043
Reaction score
1,909
I’m gonna say if true: Groundbreaking ! and kudos ...
I’m going back in for a re-read

edit add: Dang, wish you had saved the API test kit translations, Red Sea prices ..yuck! :p
Thanks for doing this!
Let me know how it goes.

@taricha and I haven’t published the API story yet. It requires the purchase of sodium citrate. Cost and hassle factor for acquiring sodium citrate for the improved API test might make Red Sea a better deal.

Besides, when you are only using 2 of the five recommended drops, the number of tests could go from 100 to 250.
 
Top Shelf Aquatics
OP
Dan_P

Dan_P

Valuable Member
View Badges
Joined
Sep 21, 2018
Messages
2,043
Reaction score
1,909
So using that pic as an approximate color card....
right to left:
0
0.05
0.1
0.2
....
etc. is the leftmost 3.2? can you fill in the blanks?

Also, anyone who has the hanna Low Range Si checker, it's prefect for this application (though a bit less common).
The table at the bottom of the post says it all :) 3.04 ppm is the darkest.
 

taricha

2500 Club Member
View Badges
Joined
May 22, 2016
Messages
3,183
Reaction score
4,181
@taricha and I haven’t published the API story yet. It requires the purchase of sodium citrate. Cost and hassle factor for acquiring sodium citrate for the improved API test might make Red Sea a better deal.

We could post it in here too since it doesn't specify Red Sea in the thread title.
 

blasterman

Valuable Member
View Badges
Joined
Feb 14, 2019
Messages
1,520
Reaction score
1,645
Question:

How does measuring Ammonia more accurately make your tank cycle faster, or more stable? Are the bacteria going to realize they are being monitored and grow faster? :cool:
 

taricha

2500 Club Member
View Badges
Joined
May 22, 2016
Messages
3,183
Reaction score
4,181
Question:

How does measuring Ammonia more accurately make your tank cycle faster, or more stable? Are the bacteria going to realize they are being monitored and grow faster? :cool:
Look. SOMEBODY'S gotta hold these bacteria accountable!
 
https://www.youtube.com/c/ReefStache

brandon429

why did you put a reef in that
View Badges
Joined
Dec 9, 2014
Messages
18,570
Reaction score
15,261
Location
tejas
knowing accurately what nh3 does in a cycling tank, and by when, currently eludes the hobby

adjustments like this help to reveal truths, and truth affects the retail market in interesting ways. being able to plan and effect stark changes in reef tanks reliably such as home moves and upgrades all rely on accurate nh3 control, I’m interested in adjustments that reveal more consistency tank to tank when basic ammonia tests are ran. this is promising.
 
Last edited:

brandon429

why did you put a reef in that
View Badges
Joined
Dec 9, 2014
Messages
18,570
Reaction score
15,261
Location
tejas
Dan did your reef tank water/known cycled water test out at the lowest possible

or mid
 

taricha

2500 Club Member
View Badges
Joined
May 22, 2016
Messages
3,183
Reaction score
4,181
For 5 mL of sample, add 0.05 mL (Salifert red scoop) of the powder reagent A (for a 10 mL sample, one level white scoop, 0.15 mL, supplied with the Red Sea should be OK).
hmm... this amount might be close. I doubled this recipe - 10 mL Tank Water sample, 2 salifert 0.05mL scoops of reagent A and I got cloudy precipitation from 10 minutes on.
I checked and my salinity was a smidge high - 1.0275 s.g.
A Red sea scoop 0.15mL of reagent A kept things nice and clear.
ReagentA 0.10mL vs 0.15mL.jpg


I might say for 5mL sample 1.5 to 2 salifert 0.05mL scoops of Reagent A.

edit: Dan, that zero color is sooo low, it makes any actual reaction color really easy to see. Very NICE.
 
Last edited:

Cory

More than 25 years reefing
View Badges
Joined
Oct 30, 2014
Messages
6,331
Reaction score
2,759
Location
Canada
I have a bag of sodium citrate and api ammonia test kit waiting to be used hint hint lol. I dont have a red sea because its hard to find where i am. Thanks for this guys!
 
OP
Dan_P

Dan_P

Valuable Member
View Badges
Joined
Sep 21, 2018
Messages
2,043
Reaction score
1,909
I have a bag of sodium citrate and api ammonia test kit waiting to be used hint hint lol. I dont have a red sea because its hard to find where i am. Thanks for this guys!
I just shared this recipe with @taricha and @Rick Mathew today. So, this is hot off the presses and not confirmed by anyone yet. You could be the first! Double the recipe for 10 mL sample

API Modified Recipe
5 mL sample
0.15 mL sodium citrate. white scoop from Red Sea kit. 3 red Salifert scoops add up to 0.15 mL
3 drops Reagent A
2 drops reagent B
Development time 1 hour
Color is a shade of sky blue

I will publish a standard curve for the PO4 Checker. Remind me if you don’t see something in 24 hours.
 
Maxout

Cory

More than 25 years reefing
View Badges
Joined
Oct 30, 2014
Messages
6,331
Reaction score
2,759
Location
Canada
I did the test on my tank water with api and sodium citrate. It turned an instant yellow color without any green hue. Am i supposed to put in the phosphate checker after an hour?
 

Cory

More than 25 years reefing
View Badges
Joined
Oct 30, 2014
Messages
6,331
Reaction score
2,759
Location
Canada
API Modified Recipe for 10 ml sample:
10 mL sample
0.30 mL sodium citrate. white scoop from Red Sea kit. 6 red Salifert scoops add up to 0.30 mL
6 drops Reagent A
4 drops reagent B
Development time 1 hour
Color is a shade of sky blue

Ill just put this here for users to follow for 10ml bottle samples (the one from hanna checker is 10ml). If its not correct let me know ill change it.
 

taricha

2500 Club Member
View Badges
Joined
May 22, 2016
Messages
3,183
Reaction score
4,181
I did the test on my tank water with api and sodium citrate. It turned an instant yellow color without any green hue. Am i supposed to put in the phosphate checker after an hour?
Yellow formation happens quickly the blue/green product takes most of the hour to fully develop.
Run it in the checker after that.
 

taricha

2500 Club Member
View Badges
Joined
May 22, 2016
Messages
3,183
Reaction score
4,181
Dan did your reef tank water/known cycled water test out at the lowest possible

or mid
My tank water (established for years) usually gives a "high zero"
Ran two samples today on the Red Sea formula
using the ULR P meter (hi736) they read 38 and 37.

Compare to Dan's standard curve data here, and you can see what I mean. I'd call it a high zero - clearly under 0.05, and not really well quantifiable in that range.

HI 736, ULR P Checker Standard Curve

0414922F-37EA-4EBB-8AD9-868AAB044457.png


In this curve you can more easily see how the standard curve drops off after 0.1 ppm. Again, we can measure down to 0.1 ppm but we can detect down to at least 0.05 ppm.

So you can see what an improvement the greater sensitivity is. Sure you could argue whether it's zero or not, but it's clearly not 0.2 or 0.25 (or even 0.1+)
 
Top Shelf Aquatics

HAVE YOU EVER BUILT A NEW HOUSE "AROUND" A NEW DREAM REEF TANK SET UP?

  • Yes (tell us in the thread)

    Votes: 5 10.9%
  • NO, but I would like to

    Votes: 30 65.2%
  • NO, I would worry about the tank later

    Votes: 10 21.7%
  • Other (please explain)

    Votes: 1 2.2%
Torch SALE
Top