Hanna phosphate checker

[Lefty McWaterbox]

So I got a Hanna set of checkers for my 6 month old water box 100.3. All my levels have been good. I ordered the phosphate tester after reading a post here. My first check was 0.1. I did a water change (I do a 5 gallon change weekly) and added some phosphate removing media. In two days it went down to 0.05. Great. Next day it was .08 and two days later (today) it is 0.13! I have been having issues with the checker in that it tells you to shake the sample for two minutes after you zero it. But it turns off after two minutes and starts over. So I’ve been collecting two samples. One to zero it out and the other to add the agent to. Could this be giving me bad readings? Everything in the tank looks happy.
Any advice would be appreciated !

 

[sghera64]

@MnFish1

 

[MnFish1]

@MnFish1

Sorry - im no expert here.... was there a question?

 

[sghera64]

Sorry - im no expert here.... was there a question?

I think the OP would benefit from you sharing what you learned from Hanna about the 2 min mix, the measurement precisely at 5 min and any concerns with using one vial to zero and one to hold sample.

I sense the OP has a defective checker, but wants to hit the 5 min mark using two vials to overcome the timer defect.

 

[Heavymman]

So I got a Hanna set of checkers for my 6 month old water box 100.3. All my levels have been good. I ordered the phosphate tester after reading a post here. My first check was 0.1. I did a water change (I do a 5 gallon change weekly) and added some phosphate removing media. In two days it went down to 0.05. Great. Next day it was .08 and two days later (today) it is 0.13! I have been having issues with the checker in that it tells you to shake the sample for two minutes after you zero it. But it turns off after two minutes and starts over. So I’ve been collecting two samples. One to zero it out and the other to add the agent to. Could this be giving me bad readings? Everything in the tank looks happy.
Any advice would be appreciated !

My understanding is the new ones they sell now have a longer timer so you don’t run into this issue. I know it doesn’t really help you with what you are dealing with now. Also they do sell calibration curvettes if you feel like checking the accuracy of yours

 

[408Dartfish]

I used to run into same problem. I try get the reagent ready by cutting it open ready to pour into vile. If its the ppm checker I believe .03 accuracy +\-

 

[killr66tb]

I have the same problem with that checker and I use two vials also works just fine

 

[MnFish1]

I think the OP would benefit from you sharing what you learned from Hanna about the 2 min mix, the measurement precisely at 5 min and any concerns with using one vial to zero and one to hold sample.

I sense the OP has a defective checker, but wants to hit the 5 min mark using two vials to overcome the timer defect.

Follow the instructions exact,y.











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[killr66tb]

Yes follow the instructions exactly you're getting the water from the same tank so it won't matter

 

[PatW]

The checker zeros out the vial with an untreated water sample in it. You should use that vial for the test. One would expect a small variation between vials and samples of tank water.

Functionally, I have found no difference using another vial with tank water in it as the control and the test vial treated vs using the test vial as its own control.

I usually run a vial as it’s own control. But I have done it the other way if I mess up. And the results I get do not deviate from doing the test normally.

You need to keep the vials clean to use different vials on the test. Having semi dirty vials would add another layer of variation. But even that might not be enough to cause a variation in the results.

 

[Alfrareef]

There are very good videos about how to do it.
I’ve tried several ways and now I just use the same vial and place a timer to make sure i maximize the 3 minutes for the powder to solve.
What you shouldn’t do is to shake the mix and try to remove the bubbles It’s better to stir.

 

[smartwater101]

I've tried using two vials but the results are never accurate. Too many variables in the way. You just have to have the reagent ready to go. I also use the timer on my phone to at least get a min and a half to shake it up.

And I always do two tests (sometimes three) just to make sure.

 

[PEP12]

I also use the Hanna phosphate checker and only use one vial, I use a timer zeroed in on 3 minutes ready, before putting in the powder I start the timer and then straight away add the powder and then let the timer run while mixing the reagent run down to 30 seconds, then put the vial into the checker to start the 3 minutes run down to the result, I do not have any issues with the checker when carrying out this method every time.

 

[reeferKen]

from reading the forums...keep the reagents capped as much as possible. That will reduce evaporation of water, which will skew the results low. Put your reagents in the refrigerator, last longer.

 

[Adamantium]

from reading the forums...keep the reagents capped as much as possible. That will reduce evaporation of water, which will skew the results low. Put your reagents in the refrigerator, last longer.

The phosphate reagent is small packets of powder, actually

 

[reeferKen]

a lot of folks have more than one Hanna

 

[MnFish1]

I think the OP would benefit from you sharing what you learned from Hanna about the 2 min mix, the measurement precisely at 5 min and any concerns with using one vial to zero and one to hold sample.

I sense the OP has a defective checker, but wants to hit the 5 min mark using two vials to overcome the timer defect.

As I said above - first you need to follow the instructions exactly - sorry the explanation got lost in my first post @sghera64 - is this what you meant?.

Since you didn't exactly say what was happening with the timer - its hard to give you a suggestion about what to do differently. No offense to the others recommending differences from the protocol ie use 2 vials, 2 different water samples - though it may seem that you're getting accurate results - you may not be - this is directly from the company (not my advice).

But if you're following the instructions exactly - this should not happen. There was a lengthy thread a while ago where we went through this - and during that I called Hanna - the results:

1. You should use the same cuvette for the zeroing and the testing (every time)
2. You should not shake the vial - as bubbles will cause problems (this is in the instructions as well
3. If you have the powder open - first - it helps.
4. Make sure you empty/clean the vial immediately or you can stain the glass and get false readings.

 

[Lefty McWaterbox]

As I said above - first you need to follow the instructions exactly - sorry the explanation got lost in my first post @sghera64 - is this what you meant?.

Since you didn't exactly say what was happening with the timer - its hard to give you a suggestion about what to do differently. No offense to the others recommending differences from the protocol ie use 2 vials, 2 different water samples - though it may seem that you're getting accurate results - you may not be - this is directly from the company (not my advice).

But if you're following the instructions exactly - this should not happen. There was a lengthy thread a while ago where we went through this - and during that I called Hanna - the results:

1. You should use the same cuvette for the zeroing and the testing (every time)
2. You should not shake the vial - as bubbles will cause problems (this is in the instructions as well
3. If you have the powder open - first - it helps.
4. Make sure you empty/clean the vial immediately or you can stain the glass and get false readings.

The instructions on my test say shake gently for 2 mins after adding the reagent. But at the end it says the timer shuts off after two minutes therefore loosing your previously completed zeroing. So I just completed a testing where I gently shook for 100 seconds , which is less than the two minutes, then put the cuvette in the meter and pressed the timer function. It worked and came back at 0.00. I also tested with my API tester which came back at zero. Last night switching cuvettes my results were 0.13. So I will double test again tomorrow.

 

[MnFish1]

The instructions on my test say shake gently for 2 mins after adding the reagent. But at the end it says the timer shuts off after two minutes therefore loosing your previously completed zeroing. So I just completed a testing where I gently shook for 100 seconds , which is less than the two minutes, then put the cuvette in the meter and pressed the timer function. It worked and came back at 0.00. I also tested with my API tester which came back at zero. Last night switching cuvettes my results were 0.13. So I will double test again tomorrow.

The other times people have had this problem they were not doing the test correctly.
So just to make sure:

you turn it on - add water to the cuvette and press the button once. Its 'zeroed' once Add C2 is shown.

You now should have 3 minutes to mix the sample (gently shaking rather than hard shaking) so there are no bubbles for 2 minutes. (if you have less than 3 minutes - your checker is defective - But you're reading the instructions incorrectly I think.

Now you put the sample in the checker. and press the button - after 3 minutes the result should show.
The checker turns off after 2 minutes

You can't accurately do the test unless you shake for 2 minutes (not 100 seconds).

 

[Lefty McWaterbox]

The other times people have had this problem they were not doing the test correctly.
So just to make sure:

you turn it on - add water to the cuvette and press the button once. Its 'zeroed' once Add C2 is shown.

You now should have 3 minutes to mix the sample (gently shaking rather than hard shaking) so there are no bubbles for 2 minutes. (if you have less than 3 minutes - your checker is defective - But you're reading the instructions incorrectly I think.

Now you put the sample in the checker. and press the button - after 3 minutes the result should show.
The checker turns off after 2 minutes

You can't accurately do the test unless you shake for 2 minutes (not 100 seconds).

I am following the process you later out. I made the change to 100 seconds due to the checker shutting off. I will check again tomorrow. But the checker has turned off on me 3 times during the 2 min gentle shake process.
Thanks for your advice. I’ll let you know how it works out.