Hanna tester

[kp33]

Using the Hanna tester for the first time for phosphates, yesterday got a reading of .19 which is about right, today did a test it read .46 which I thought there’s no way it went up that much overnight, did another one it’s .17 so my question is what caused the .46 reading, does that happen from time to time, did I do something wrong, with this test is there something I need to make sire I’m doing or not doing? Thanks

 

[Pistondog]

The hanna testers use light shining thru the vials to,read color. Try to orient the vials the same when "c2"ing, and reading test results. Make sure the vials are clean.
Correctly, you doubted strange results and retested.

 

[SchrutesReefs]

Also be sure that you don’t have fingerprints or smudges on the glass as it will affect the readings pre-or post reagent

 

[kp33]

What do you mean when you say orient the vials at the same time? I put the vial in with no powder to c2 it, then I add the powder and run the test.

 

[homer1475]

Orient the cuvette the same way each time you put it in the tester. Small variations in the glass can cause imperfect readings.

Meaning:
What I do is put the cuvette in th etester with the I in the Hanna Instruments facing forward every time I put it in the tester. Or even easier is to just make sure the "10" on the 10ml line is facing forward.

 

[Pistondog]

What do you mean when you say orient the vials at the same time? I put the vial in with no powder to c2 it, then I add the powder and run the test.

There is a "10ml" label on the vial. Try to make sure it is on the same side before and after powder. This would eliminate any difference in vial clarity based on orientation. As you use the vials, they may get scale or dirty spots.

 

[kp33]

Oh ok I see what you mean wow it’s that sensitive huh.

 

[Pistondog]

Also, make sure the vial is dry before insertion into the tester.

 

[kp33]

Yeah that I did I dried the outside after I added the water and before putting in the unit.

 

[SchrutesReefs]

Oh ok I see what you mean wow it’s that sensitive huh.

Yes, but IME it’s the most accurate when used properly.

 

[kp33]

Got ya just got to be the same every time to make sure no false readings, so when I’m adding the powder and shaking the lid to the unit has been open does that need to be closed while adding and shaking the powder does that make a difference?

 

[homer1475]

How are you shaking it? With your finger over the top? Not a good practice, and anything on your finger, could skew the results.

Yes put the lid on after adding the reagent.

FWIW.....
If you haven't watched the youtube video from hanna on how to cut the reagent packet, and the proper procedure for using the checker, I suggest you do. It will help a ton with the proper procedure, and how to fold the packet so you get all the regent out(hanna has stated there is more reagent then what's needed to perform the test, so getting every miniscule amount of reagent out of the packet isn't extremely important).

 

[kp33]

No when shaking I have the lid on what I meant was the lid to the actual unit is open when I’m shaking it not the lid to the vial.

 

[homer1475]

My procedure.....

Clean vial with tap water, rinse cuvette in tank water, fill with 10ML of tank water with syringe(the 10ml line, isn't very accurate either), place cap on cuvette, clean cuvette again so it is dry, and fingerprint free.

Cut reagent packet and fold according to their you tube vids, turn on checker, insert cuvette into the checker for c1, press button, wait for C2, remove vial, unscew cap, add reagent, replace cap, gently shake up and down with fingers on the bottom, and top(no fingers on the glass sides where the checker reads from), shake for 2 minutes, put back in checker, press and hold the button for the timer.

 

[homer1475]

No when shaking I have the lid on what I meant was the lid to the actual unit is open when I’m shaking it not the lid to the vial.

I got you now. I leave my lids open too, don't think it matters.

 

[cgripp256]

I think the OP is reinserting the vial into the reader before shaking. I don’t think that is necessarily wrong but I shake mine outside and then wipe and re-insert. That way I can make sure the reagent is fully dissolved and there are no bubbles.

 

[kp33]

No I’m shaking before I put back into tester.

 

[Lasse]

I have an aquarium with many small particles. I have found that the phosphate checkers is very sensitive for particles in the water - even if you can´t see them with your bare eye. Nowadays - I always filtrate my samples over a syringe filter of 0.2 µ. I get more realistic and stable result this way

Sincerely Lasse

 

[homer1475]

I have an aquarium with many small particles. I have found that the phosphate checkers is very sensitive for particles in the water - even if you can´t see them with your bare eye. Nowadays - I always filtrate my samples over a syringe filter of 0.2 µ. I get more realistic and stable result this way

Sincerely Lasse

I actually found the same. So when I originally bought the low range nitrate checker, loved the little filter it comes with. I cannibalized that checker, and put all my samples through that filter now.

Great tip, and one I do all the time now, and don't think of mentioning it!

 

[cgripp256]

I actually found the same. So when I originally bought the low range nitrate checker, loved the little filter it comes with. I cannibalized that checker, and put all my samples through that filter now.

Great tip, and one I do all the time now, and don't think of

No I’m shaking before I put back into tester.

well there goes my theory