Discrepancy between Hanna Nitrate HR VS old school API

[douglasbnyhof]

Just bought the new Hanna HR nitrate kit. It tested to 72 ppm which is alarming but the API tester says 0 (The light yellow color). I ran the test several more times on other tanks making sure the countdown was counting down. The other tank was 0 on API and the HANNA was 52.

ANYONE else have anything new to add over what has already posted ?

 

[Idech]

That is extremely weird. Can you test new saltwater with both test kits ? It should be close to 0 for both.

 

[douglasbnyhof]

That is extremely weird. Can you test new saltwater with both test kits ? It should be close to 0 for both.

Great idea. I’ll do this. Don’t know why I didn’t think of it.

 

[douglasbnyhof]

Great idea. I’ll do this. Don’t know why I didn’t think of it.

That is extremely weird. Can you test new saltwater with both test kits ? It should be close to 0 for both.

Tested the clean salt water and both read 0.0

 

[Idech]

Tested the clean salt water and both read 0.0

I would trust the Hanna more than the API then. API is usually kind of okay though, even if not precise. Did you do the shaking exactly as it says in the instructions. That’s really important.

 

[Cycleguy0623]

I would trust the Hanna more than the API then. API is usually kind of okay though, even if not precise. Did you do the shaking exactly as it says in the instructions. That’s really important.

I second the shaking. I have noticed that if I don’t use a timer and shake aggressively I get odd readings.

 

[douglasbnyhof]

I second the shaking. I have noticed that if I don’t use a timer and shake aggressively I get odd readings.

I’ll shake harder.

 

[xmjxflipx]

Hanna is highly accurate.. for API just remember u gotta shake bottle #2 on API for a minute vigorously

 

[Homestarmy]

I stumbled across this thread while trying to research why my Hanna Marine Master is reading is so much lower than either the API or Red Sea test kits.

Here's the background - I've only been at this for about 7 months and, in that time, I jumped from API to Red Sea test kits due to concerns about accuracy, but those seem to be a bit unfounded as the readings seemed to be relatively close in most cases. I recently decided that I'm going to drive myself nuts trying to determine which shade of yellow/orange/blue a particular test result yields, so I decided to go digital and picked up the Marine Master when it went on sale recently.

Testing Nitrate with the API/Red Sea had been resulting in readings in the 40-50ppm range, so imagine my surprise when my first reading with the Hanna was 1.3ppm! While potentially delighted, I was obviously skeptical.

I retested this morning with the Hanna and the Nitrates came in at 6.5ppm, which still seemed low, so I tested with the API (I'm out of one of the Red Sea reagents, so no verification there). The result from the API test was in that 40ish range, so I decided to do some research and came across this article API Nitrate Reagents 'Usable' with Hanna Checker which laid out the steps to use said reagents, so I did. This time the Hanna reading was 11.3ppm, even though the color was actually the same as the straight API test (which tells me the samples were equivalent).

So, Now I'm completely confused. I like the idea of testing both against clean salt, which I will do tomorrow as part of my water change, and I realize the article mentioned the Hanna Checkers and not the Marine Master, but I have to think that it would work on both platforms. I guess I'm just looking for any input/advice/thoughts on the subject.

 

[xmjxflipx]

Homestar army i remember one time i had a bad batch of nitrate hr reagants and got replacements for free from contacting hanna on huge discrepancy. Do multiple repeat hanna reagant rests but first rinse wirh rodi water. For my situation about half was showing good and the other half showed very small amount of nitrates compares to results. It shoulnt be so far off where red sea pro is 60 and hanna is 11.3. i enver know how vigorously to shake so i try to personally first shake 6 times, 10 seconds shake then pause, then shake again then thr last 60 seconds do s continuous shake for 60 seconds really vigorously.

 

[Garf]

Just bought the new Hanna HR nitrate kit. It tested to 72 ppm which is alarming but the API tester says 0 (The light yellow color). I ran the test several more times on other tanks making sure the countdown was counting down. The other tank was 0 on API and the HANNA was 52.

ANYONE else have anything new to add over what has already posted ?

Probably the best way to know, is to make a standard nitrate solution that you can dilute with fresh saltwater to calibrate any nitrate test kit, for the rest of your life. I've got a litre of 6100ppm solution for such occasions (I've also got a phosphate reference solution), they are cheap to DIY. Looks like I used 10grammes of potassium nitrate per litre of RODI;

Do Hanna Checkers have different colour LEDs?

I only have one checker, the Phosphate LR. The LED colour is green, same as the casing, as it happens. Am I right in thinking other checkers have different colour LEDs to take readings more effectively, depending on the colour change of the solution under test? I bring this up as I’ve tried...

www.reef2reef.com

 

[MrGisonni]

Make sure first of all your 10 mL collection is accurate. I actually found the reagent packet with the back of a scissor to make sure it's completely fine powder. I use the tiny funnel and open up the packet entirely and make sure every last bit of powdered reagent gets in my sample. I set a timer and shake for 2 minutes. All the while I make sure that the curvette is clean. The henna testers can be a little fickle if you don't follow the instructions exactly.

 

[Homestarmy]

Good advise, thank you. I haven’t ground the reagent, but I’ll give that a try and I am mindful of getting the measurement correct, and I do follow the shaking directions to the letter. Although I’m curious about the funnel - I just form the packet into a funnel, is that what you’re referring to or is there an actual funnel in the kit that I’m missing? Also, how do you clean your corvette? I clean as I go immediately rinsing with ro water before moving on to the next test.

 

[Homestarmy]

Probably the best way to know, is to make a standard nitrate solution that you can dilute with fresh saltwater to calibrate any nitrate test kit, for the rest of your life. I've got a litre of 6100ppm solution for such occasions (I've also got a phosphate reference solution), they are cheap to DIY. Looks like I used 10grammes of potassium nitrate per litre of RODI;

Do Hanna Checkers have different colour LEDs?

I only have one checker, the Phosphate LR. The LED colour is green, same as the casing, as it happens. Am I right in thinking other checkers have different colour LEDs to take readings more effectively, depending on the colour change of the solution under test? I bring this up as I’ve tried...

www.reef2reef.com

Probably the best way to know, is to make a standard nitrate solution that you can dilute with fresh saltwater to calibrate any nitrate test kit, for the rest of your life. I've got a litre of 6100ppm solution for such occasions (I've also got a phosphate reference solution), they are cheap to DIY. Looks like I used 10grammes of potassium nitrate per litre of RODI;

Do Hanna Checkers have different colour LEDs?

I only have one checker, the Phosphate LR. The LED colour is green, same as the casing, as it happens. Am I right in thinking other checkers have different colour LEDs to take readings more effectively, depending on the colour change of the solution under test? I bring this up as I’ve tried...

www.reef2reef.com

That’s interesting, never thought of that to be honest, but I will look into it. Thank you!

 

[Homestarmy]

Homestar army i remember one time i had a bad batch of nitrate hr reagants and got replacements for free from contacting hanna on huge discrepancy. Do multiple repeat hanna reagant rests but first rinse wirh rodi water. For my situation about half was showing good and the other half showed very small amount of nitrates compares to results. It shoulnt be so far off where red sea pro is 60 and hanna is 11.3. i enver know how vigorously to shake so i try to personally first shake 6 times, 10 seconds shake then pause, then shake again then thr last 60 seconds do s continuous shake for 60 seconds really vigorously.

I wonder if that’s not a part of the problem (or all of it). I’ll be very curious to see what the results are after I make that fresh batch of water tomorrow and test it against each of the checkers!

 

[Uncle99]

The Hanna HR nitrate tester has worked very well for me, year over year.

API works, but I’m concerned it’s not fine enough.