Hanna Phosphate checker

[Trav0023]

I've been using a Hanna Phosphate checker for the past few months and having gone through the 30 reagents that I got with the unit when ordered it, I've purchased another 25 pack. Immediately I noticed the amount of powder was not equal to the previous packets and the results reflect that.

There is no indication on the packets themselves of a specific weight or volume of powder that should be contained or used for testing.

Has anyone else experienced this? Although I want to believe that my PO4 problem has been cut in half the growth of the Diatoms and pineapple sponges suggests otherwise so now I'm having trust issues with the Hanna checker itself.

 

[Randy Holmes-Farley]

The amount of reagent in a phosphate test like Hanna uses should not be the limiting factor in hte phosphate determination. In other words, there should always be a big excess of it, at least until you hit the max phosphate level the device can detect. Doubling the reagent should not make all that much difference, except perhaps some extra background absorbance of the baseline (0 phosphate).

That said, I can't be sure that the packets you got are properly manufactured.

 

[Trav0023]

The amount of reagent in a phosphate test like Hanna uses should not be the limiting factor in hte phosphate determination. In other words, there should always be a big excess of it, at least until you hit the max phosphate level the device can detect. Doubling the reagent should not make all that much difference, except perhaps some extra background absorbance of the baseline (0 phosphate).

That said, I can't be sure that the packets you got are properly manufactured.

So the amount of reagent in each package is irrelevant to the reading?

This is a screenshot of the change I have experienced, I did not include the first result on the 28th it was around .54 PPM and I believed it was not realistic. I did a double water change on the 1st, around 100 gal or 15% system volume.

Thanks

 

[Randy Holmes-Farley]

So the amount of reagent in each package is irrelevant to the reading?

This is a screenshot of the change I have experienced, I did not include the first result on the 28th it was around .54 PPM and I believed it was not realistic. I did a double water change on the 1st, around 100 gal or 15% system volume.

Thanks

It isn't irrelevant, but the amount of reagent in such a test is not typically critical enough to cause large differences. I would always try to use all the reagent supplied, but not get worried that the packet volume looks different. It may just be that the form of one of the ingredients changed (particle size changes, for example). Or maybe they actually reformulated it a bit. I can't know what exactly they are doing in manufacturing.

It looks like the last measurement is coming back up toward your more typical range, right?

 

[Trav0023]

It dose look that way but it is still only a .84 compared to the previous readings of 1.20 - 1.40, I'll run another test tonight to see where it's at.

Thanks For your feedback.

 

[Randy Holmes-Farley]

In terms of husbandry, all of them are basically the same: too much.

 

[Trav0023]

In terms of husbandry, all of them are basically the same: too much.

agreed. I think it's being released from the live rock the tank is just over 3 months now so I'm hoping it will start to drop off soon. I've been adding sugar cubes along with a VSV carbon dosing program to try to get the good bacteria up and drive the number down.

 

[Trav0023]

So I used up the 25 pack discussed above and have now started into a new lot (different lot # production run) and consistency has returned to the results.

 

[ckozma]

What software are you using to track that? Is that just a function of the Apex? A place to enter all of that testing data? Because I know that Apex doesn't test for phosphates...

 

[Oceansize]

I was just online earlier today buying another 25-pack of reagent for my Hanna phosphate checker and noticed there's a very similar-looking packet for their High-Range Phosphate checker. Ours are the low-range checker. That might be an explanation to look into.

 

[aaron23]

hanna quality can not be relied upon... in jan i bought my first 3 hanna checkers and 2 of the 3 gave me consistently WRONG RESULTS. Bad Calcium checker results in +100 ppm, alk checker is all over the place. lost my confidence in their products just when i thought they'd be reliable.

 

[Oceansize]

hanna quality can not be relied upon... in jan i bought my first 3 hanna checkers and 2 of the 3 gave me consistently WRONG RESULTS. Bad Calcium checker results in +100 ppm, alk checker is all over the place. lost my confidence in their products just when i thought they'd be reliable.

When I use the Hanna phosphate checker, I always fill both vials and use one as my "control" vial while putting the reagent in the other. Then I conduct the test several times in a row, switching back & forth between the two vials. Every time I do, I get a range of results, but they are ALWAYS within +-0.04 ppm of each other, which is exactly the same as the margin of error they claim the device to have. I'd like there to be a smaller than +-0.04 margin of error considering the sweet spot is 0.02-0.03, but at least it's working as advertised, and is WAY better than the +-0.25 margin of error for the API test, lol. It IS frustrating trying to know if my phosphates are at 0.03 yet when the test gives me a range of 0.06 to 0.02, but I can't think of a better test that isn't several hundred dollars.

 

[Vaughn17]

For their phosphate test, I find that it is impossible to get all the reagent to dissolve by "gently shaking" in the 1.5 minute time frame that is alloted. Shaking harder creates micro bubbles that alter the result and still does't dissolve all the reagent. Does all the reagent need to be dissolved?

 

[Oceansize]

For their phosphate test, I find that it is impossible to get all the reagent to dissolve by "gently shaking" in the 1.5 minute time frame that is alloted. Shaking harder creates micro bubbles that alter the result and still does't dissolve all the reagent. Does all the reagent need to be dissolved?

Yes it does, and this is why I use both vials. Fill both vials with tank water, then completely dry & clean the outside of both vials. BEFORE turning on the checker and starting the annoying countdown, add the reagent to the second vial and gently swirl (not shake) for 2 minutes. THEN turn on the checker, and use the OTHER vial for the first part of the test. Done this way, you're adding reagent to the vial WITHOUT trying to beat a 3-minute countdown. You still have to be relatively quick, as the test results will be less accurate within a decent amount of time, but at least it's not some crazy race against the clock.

For my first round of testing, I do follow the instructions and HOLD the button while checking the vial with reagent in it in order to start another, different 3-minute countdown. For subsequent rounds with the same two vials, I simply press the button rather than hold it, since the reagent has now definitely been dissolved long enough.

 

[Vaughn17]

Thanks, but I have tried that. I can never get the same result twice.

 

[Vaughn17]

Good to know all the reagent has to be dissovled, though!

 

[Oceansize]

Thanks, but I have tried that. I can never get the same result twice.

As long as your results are within 0.04 ppm of each other, the checker is working just fine.

Just yesterday I put the same two vials through the checker five times. My first reading was 0.08. My second was 0.04. The next three were all 0.05. I would take these results to mean that my phosphates are 0.05 even though my first reading was 0.08.

 

[djbetterly]

I really like my hanna checkers and treat their results no different than I did any other test (red sea, elos, etc), I test everything 2-3 times and average the results. They have good products and from past experience any error is due to human error, or scratched, dirty cuvettes. Its very important that the cuvettes stay incredibly clean.

 

[Gomery12]

What software are you using to track that? Is that just a function of the Apex? A place to enter all of that testing data? Because I know that Apex doesn't test for phosphates...

Bump!
I would like to know as well!

 

[djbetterly]

There is a place to input all of your testing results within Apex. See screen shot.