Neptune Aquatics

Hanna phosphate test kit questions.

Dongta408

Dongta408

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Hi guys i confused about hanna testing, here what i had last 3 package testing, each package testing i tested 4 times. (Each time have different values results)

Package 1: a) 0.16 b) 0.15 c) 0.06 c) 0.04
Package 2: a) 0.23 b) 0.21 c) 0.05 c) 0.03
Package 3: a) 0.18 b) 0.17 c) 0.02 c) 0.01

Each package was taken 48 hours different. Please be advised. TIA
 
with those testers i don’t think you will ever get a “Rock solid” confirmed number. i would just average the numbers out and call it good.
I would not worry unless the readings were like 3.00 or higher consistently.
 
Coral reefer said:
I don’t understand what you mean by package? You mean packet of reagent powder? Or package (box) if packers od reagent powder?
How are you testing 4 times?
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Probably with two vials. I use two also since the tester turns off if you don't add the second vial quick enough.

Also same here, numbers decrease as you test multiple times. Maybe as reagent sits in the vial the reading gets weaker somehow
 
igcreef said:
Probably with two vials. I use two also since the tester turns off if you don't add the second vial quick enough.

Also same here, numbers decrease as you test multiple times. Maybe as reagent sits in the vial the reading gets weaker somehow
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Dump the powder out into a laminated playing card or business card folded in half ahead of time. That way you’ll have enough time.
 
Not about how quick you pour the powder package to vitals. Here what i did, i have 2 vitals tank water really, 1 fill with powder reagents, one not. Follow the test kit process and repeat ( remember you have to have a vital with the tank water only to alternate the process. )
 
Dongta408 said:
Not about how quick you pour the powder package to vitals. Here what i did, i have 2 vitals tank water really, 1 fill with powder reagents, one not. Follow the test kit process and repeat ( remember you have to have a vital with the tank water only to alternate the process. )
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You are suppose to use the same cuvette with the same water throughout the testing process. Steps C1 and C2 needs to be with the same cuvette and same water. Don’t switch out the cuvette with a different one. Make sure the 10ml mark on the cuvette is facing the left hinge every time. Cut the reagent packet ahead of time. You also don’t need to shake it the full 2 minutes just as long as all the reagent has dissolved. Also, wipe down the cuvette before placing it in the checker. The oils from your skin can throw off the results. Consistency is key when testing your water parameters. Gotta do everything exactly the same, every time.
 
Mr2KiEu said:
You are suppose to use the same cuvette with the same water throughout the testing process. Steps C1 and C2 needs to be with the same cuvette and same water. Don’t switch out the cuvette with a different one. Make sure the 10ml mark on the cuvette is facing the left hinge every time. Cut the reagent packet ahead of time. You also don’t need to shake it the full 2 minutes just as long as all the reagent has dissolved. Also, wipe down the cuvette before placing it in the checker. The oils from your skin can throw off the results. Consistency is key when testing your water parameters. Gotta do everything exactly the same, every time.
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Never knew about the 10mL facing the hinge but will continue doing that. Does the marker obstruct the sensor otherwise?

for pouring the powder I like to get it ready to pour before starting the testing process so it’s quick to pour in. I cut it and fold it so it can pour down the fold, I shake it gently with the packet straight up before pouring so it will pour out all together without too many clumps.
 
It is about time with the reagent because you are supposed to use the same cuvette (vial) for both parts of the test, not switching between the two.
And yes the timing of the test matters which is why you are seeing different results over time.
 
I always did like what you said... but one day my phosphate out off my range, so i fill up another cuvette with the tank water and reruns the test again, the more i retest the more i get different values, my question is , first number is correct number? ( this is same package reagent)
 
Coral reefer said:
It is about time with the reagent because you are supposed to use the same cuvette (vial) for both parts of the test, not switching between the two.
And yes the timing of the test matters which is why you are seeing different results over time.
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Time between test only couple minutes... would be made that difference? Just wonder..
 
I think you are supposed to wait 3 minutes. It should say in the directions. I think you’ve seen that it does matter with the number you posted before.
 
Ok guys. I did this for my experience, not to confuse anyone. Of course i understand how the test process.
C1= tank water
C2= tank + reagent
Now I have 2 cuvette. One had reagent, one not
After run the first test, i turn off the device and perform the test again. My question is why the value is different? I did the same thing with KH and the value always the same. Why not the same with phosphate? If different .01 - .04 is acceptable but different .17 - .03 should be concerned? Should we recalibration test kit device? I saw Hanna sell phosphate calibration kit. Just the thought.
Side note i do have Salifert tests kit to compare, so i know my parameters is good.
 
I always hold down the button after add c2 and it starts a 3 min count down. Many nitrate tests have you wait a certain amount of time before comparing color, so I assume 3 minutes is the proper reaction time. Been awhile since I read the directions tho.
 
I don’t think the directions say you must use the same vial. I always use one for tank water and one with tank water and the reagent. I hope I’m not wrong.

are you mixing the reagent for the full two minutes and then waiting 3 minutes to get the reading and yes, you should only test once and take than number. If you keep testing the reagent the numbers will change because the reaction will change over time.
 
It's generally best to use the same vial- the two vials may have different levels of clarity naturally, or maybe even a random smudge or speck on one and not the other.

You want to ensure the unit's C-2 reading taken (after the powder has been added and shaken for two minutes) is based on the same glass section and clarity level that the level-set C-1 reading taken with just tank water.

The longer the reagent mixed water stays in the vial, it will tint the glass blue ever so slightly - so you can see why you want consistency in your vial's reading- vial 1 may be clearer than vial 2, and that will affect the optical accuracy, and give you a bad test result

It helps to get everything prepped prior to switching the Hanna on -- get 10ml of tank water in vial, cut open reagent packet alonf the dashed lines, and fold it upon itself so you have funnel like corners to easily pour the powder out; set a 3 min timer and go.

Also, give the vial a good wipe with something lint free just before you stick it in the unit - as other have said: use the same orientation each time- ensuring the optical reading is taken from the same part of the glass each time. You should have plenty of time before the unit powers down.
 
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