Hanna phosphorus 3 min timer issue... found a workaround.

[kris2001]

I'm using Hanna phosphorus HI736 ULR...
i found a way to not mix the reagent in a hurry to test it within that stupid 3 min or so time limit.

I use 2 of their glass tubes. I Miix reagent in one with sw. Shake it well for 4 min. Let sit.

I use another tube for the C1 test to calibrate(?)sw.... then i pour out sw and pour in the previous mixed reagent water. And press C2 Wait 3 min till timer goes away.

Then read the phosphorus no....

Is this method ok?

I think it should be since only the * same* one of the 2 tubes goes into the unit both the times(sw, reagent salt water) .

Btw today's test was P ppb 9=almost. 03ppm.

Thanks.....

Pls advice....

 

[Crabs McJones]

I ran into the same issue. It tells you to take out the tube and add the reagent, and shake for 2 minutes. By tge time your 2 minutes is up the checker has auto turned off.

 

[NY_Caveman]

The longer it sits with the reagent though will change the color I believe. The time they are together is important.

I open the packet and have it ready before I start the process and that helps.

 

[dealseer]

I’ve never had this problem.

 

[Crabs McJones]

The longer it sits with the reagent though will change the color I believe. The time they are together is important.

I open the packet and have it ready before I start the process and that helps.

This was my first time testing with this, I actually just got the test kit today lol. I'll try having the reagent ready before hand next time

I’ve never had this problem.

..thanks

 

[NY_Caveman]

This was my first time testing with this, I actually just got the test kit today lol. I'll try having the reagent ready before hand next time


..thanks

I do always feel I am racing to get it done still.

 

[NY_Caveman]

http://blog.hannainst.com/checker-best-practices

 

[NY_Caveman]

Also, using two separate cuvettes would not seem to be a good idea. The light is doing a comparison. If one tube is say more stained than another, the result would not be apples to apples.

 

[GoVols]

Also, using two separate cuvettes would not seem to be a good idea. The light is doing a comparison. If one tube is say more stained than another, the result would not be apples to apples.

Had the same issue between the 2 vials.

Went outside, through one of them as far away as I could. (It felt really good)

Now, I pre-pour all the power onto wax paper and just use one vial. The power just slides right into the vial and I don't feel that I have to be in such a hurry.

 

[Velcro]

Apparently I need to make a video on use of this meter because I have literally never had the thing time out.

 

[NY_Caveman]

Apparently I need to make a video on use of this meter because I have literally never had the thing time out.

Honestly, reading issues people had with this meter really prepared me the first time I used it. So thanks to them.

 

[Tklb]

I always have the packet open and ready to pour then I setup the C.1 Test. Once it shows C.2 I take out the vial, add the Reagent, Shake for 2 Min, and put it back in the Checker. I believe that the Sleep/timeout is about 3 min, so you don't really have time to screw around.

 

[olecaptainj]

All these years they have been out with step by step instructions, videos, and pictures some ppl still can’t use them correctly...wow

 

[xCry0x]

My biggest problem is I set the 3 minute timer then start doing something else and completely forget to check the results. I need a checker with push notifications

 

[kris2001]

Also, using two separate cuvettes would not seem to be a good idea. The light is doing a comparison. If one tube is say more stained than another, the result would not be apples to apples.

I'm ***not using 2 separate test tubes**** into the meter. As my post says....i use second vial only to mix in advance.

The *same* vial goes into meter each time... during C1 & C2.

So the glass thickness, imperfections won't matter imo.

Instead of doing test within few mins. I mix in
Advance and take an extra 2 mins more.

Pls read my post again.... thanks!

 

[Randy Holmes-Farley Verified Community Expert]

I do not know the data behind the 3 minute timer set by Hanna, but I would not assume it is OK to intentionally trick it into allowing longer times.

I do know that the ascorbic acid method for phosphate typically has short and long allowed time limits of the absorbance measurement. It's not a Hanna-only invention.

Before I used something outside the allowed time specified by Hanna, I'd verify that it gave the same results as a time within the allowed time limit.

 

[TX_Punisher]

The issue I have is that the powder does not dissolve for me completely after 2 minutes or even 2 1/2. Once I stop shaking and let it settle, you can still see undissolved particles.

 

[Randy Holmes-Farley Verified Community Expert]

The issue I have is that the powder does not dissolve for me completely after 2 minutes or even 2 1/2. Once I stop shaking and let it settle, you can still see undissolved particles.

Most test like this have excess reagents, so as long as the final bit of particles settle out of the light beam path, that may be ok.

 

[kris2001]

I do not know the data behind the 3 minute timer set by Hanna, but I would not assume it is OK to intentionally trick it into allowing longer times.

I do know that the ascorbic acid method for phosphate typically has short and long allowed time limits of the absorbance measurement. It's not a Hanna-only invention.

Before I used something outside the allowed time specified by Hanna, I'd verify that it gave the same results as a time within the allowed time limit.

Hi Randy,
Did what you said same day ie test with my two vial method and test with one vial method(recommended method).

Remember, I'm ***not using 2 separate test tubes**** into the meter. ...i use second vial only to mix in advance... mixing for 3-4 min.

Issue with Hanna allowed time limit is it's approx 2 min 40 sec... till it turns off.
I only mix well for lil over that time maybe a min or 2.

Results today;
My two vial gave 9ppb phosphorus.
Single vial test gave 6ppb phosphorus.

These differences can happen even in the repeated tests of the same method, same day since the ULR P test is very minute/ accurate.... but in ppb.

Any thoughts?!

 

[Randy Holmes-Farley Verified Community Expert]

Hard to tell if the time mattered or not.