Accurate NO3 Test with Hanna ULR P Checker

[Rick Mathew]

Hey I just purchased a Hanna phosphate checker. But mine isn't the Ultra low version, just the regular. Will using the Red Sea nitrate reagent work with this checker for checking nitrate? Or is the Ultra low version required?

Very good question

If you are talking about the HI-713 the light diode (the source) is the same wavelength (525nm) as the HI-764...I don't know about the detectors capabilities (LR vs ULR) ....I know that the HI-736 ULR Phosphorous works as described in my other post ...but the detector was limited in it's range which is why I continued to explore other options....You would need to set up a set of experiments to see if it will work....If you are interested in the procedure I can share it with you...hope this helps

 

[Rick Mathew]

Just for consistency (albeit may not matter much)- why not make your C1 the same composition as the test vial? If you are testing 1/10th sea water make your C1 vial the same?

Another good question...anything that increases the precision and accuracy I am in favor of...I can quickly checkout the effect..thanks for your help and ideas and questions

 

[BradW]

Thanks Rick. I have the HI-713 so I would be interested in the details of your test procedure.

 

[BradW]

Thanks Rick. I have the HI-713 so I would be interested in the details of your test procedure.

 

[ckalupa]

Another good question...anything that increases the precision and accuracy I am in favor of...I can quickly checkout the effect..thanks for your help and ideas and questions

Just thinking that there are items in our water column that could affect the coloring of the baseline (meds, food, general turbidity,etc) that would make the slight changes possibly relevant especially when we are testing such small quantities of the test waters. I am doing this on the Nitrite tester method.

 

[Rick Mathew]

Thanks Rick. I have the HI-713 so I would be interested in the details of your test procedure.

I have attached an draft of my test protocol development process...It is by no means complete in all of the details of the process, but it should give you a clear idea of how to go about developing a test protocol for the HI-713 if it is suitable for this use...Step 1 Should tell you this....hope this helps feel free to ask any questions you like and I will help if I can

rick

 

[yap]

Thanks so much for this! This technique has saved me some headache.

 

[Rick Mathew]

Thanks so much for this! This technique has saved me some headache.

You are totally welcome. My pleasure. Let me know how it's working for you.

 

[Gogi]

Is this method done using Hanna Phosphorus or Phosphate checker?

 

[Rick Mathew]

Is this method done using Hanna Phosphorus or Phosphate checker?

The Hanna HI-736 ULR Phosphorous Checker....There is a second method using the HI-764 ULR meter ....The test procedure is the same but a different Tester an a different Regression formula.... Link here... https://www.reef2reef.com/ams/test-meter-for-testing-nitrates.599/ This procedure expands the testing range

 

[Silent]

Did anyone find out if this method works with the HI-713?

 

[Rick Mathew]

Did anyone find out if this method works with the HI-713?

Not sure...Have not seen any updates from @BradW who I think was interested in checking this out

 

[Gogi]

So I did the method from the first post with HI-736 and 1/10 dilution. But the result came out of range for the checker. My other test kits show value of around 2ppm. Did I understand correctly that the method range should cover that?

 

[taricha]

No. The original directions are that a 1/10 diluted sample ought to be between 0 and 1.6 ppm, so It works if your original water was between 0 and 16ppm NO3.

 

[LARedstickreefer]

My Red Sea low range nitrate tests at “0”. Am I right to assume that I can use the Hanna ULR phosphorus test, undiluted, to get an accurate read?

 

[taricha]

My Red Sea low range nitrate tests at “0”. Am I right to assume that I can use the Hanna ULR phosphorus test, undiluted, to get an accurate read?

maybe not. If the eye looking very carefully can detect no pink color at all, then the ULR P meter won't read it either <0.1ppm. (NO3 is frequently just zero. no matter how close you look.)
If however there is any barely eye-detectable color to the sample, the checker will give you a number and let you quantify it.

 

[burningbaal]

My Red Sea low range nitrate tests at “0”. Am I right to assume that I can use the Hanna ULR phosphorus test, undiluted, to get an accurate read?

Probably, but you've extrapolated past the curve, so it should get a new standard series, which is a lot of work. It's very normal for lab grade optics to detect things our eye can't see, but I can't say the grade of these optics, nor how much the tank water might interfere.
First, I'd say to make up brand new saltwater, run the test (with the checker) and also check some tank water. If they give different readings (consistently), you've probably got a good chance.
I'd then try spiking some potassium nitrate (weight to weight) into the new saltwater to make your curve.

 

[Richard Hercher]

Any thoughts on using this procedure (or similar) with the HI-774 ULR Phosphate tester?

 

[taricha]

yes. In fact the checker used in this thread hi736 and the hi774 are going to differ mainly just in the units they display, hi736 = ppb Phosphorus, hi774 = ppm Phosphate.
So to convert P ppb and PO4 ppm:
(Phosphorus ppb) * 3.066 / 1000 = (Phosphate ppm)

so to approximately convert between the checkers
[hi774 reading] * 1000 / 3.066 = [hi736 reading]
then you can use the results of this thread.

Overall, @Rick Mathew thread here - using more common NO3 Pro test kit and a different meter with a higher range gives more reliable result over a more applicable nitrate range. It's what I currently use.

 

[purp]

Probably, but you've extrapolated past the curve, so it should get a new standard series, which is a lot of work. It's very normal for lab grade optics to detect things our eye can't see, but I can't say the grade of these optics, nor how much the tank water might interfere.
First, I'd say to make up brand new saltwater, run the test (with the checker) and also check some tank water. If they give different readings (consistently), you've probably got a good chance.
I'd then try spiking some potassium nitrate (weight to weight) into the new saltwater to make your curve.

When you say weight to weight, do you mean weight of fluid vs weight of kno3 added?

 

[Randy Holmes-Farley]

When you say weight to weight, do you mean weight of fluid vs weight of kno3 added?

I presume that is what is intended, with the further assumption that folks may be able to measure liquid mass (weight) more accurately than liquid volume.