Question about Hannah phosphorous checker readings

[TRPlacek]

I have been using the Hannah hi713 for several months and was always getting a reading of 0.00 ppm. I also had issues with color fading on sps but just to make sure before I started dosing phosphates I purchased a Hannah ulr phosphorous checker. My first test came up 3ppb or .009 ppm. So I proceeded to dose 1 ml of neophos in my 100 gallon tank. I tested the next day same time and got 19ppb (.058 ppm) I then tested again as this didn't seem right to me and got 4ppb (.012 ppm) which seemed in line with what I dosed. However I decided to do one more test to make sure and I got a reading of 15 ppb (.045 ppm).

Which number should I be going off of? Did I possibly get some detritus in the vial on the higher readings?

 

[120reefkeeper]

I can't remember what the margin of error is out of the box, but you might want to check that. Unfortunately the Hanna ulr is not a lab grade checker.

 

[TRPlacek]

Do you mean margin of accuracy? It says it is + or - 5ppb. That still wouldn't make sense with the numbers I was getting. I know it's not lab grade but it seems a lot of people use it and have had success with it.

 

[TRPlacek]

I will add that since adding the NeoPhos it appears that my reds are beginning to darken and my no3 dropped to 3ppm from 4ppm which is what I was told would happen after I added the neophos.

 

[Reefnewb]

Mine can be all over the charts too. kinda a bummer

 

[TRPlacek]

Mine can be all over the charts too. kinda a bummer

It really is. I should have just saved the $50 and stuck with the hi 713. Lol

 

[Reefnewb]

It really is. I should have just saved the $50 and stuck with the hi 713. Lol

Yeah I shouldn't have even got one, because I get a better idea of Phosphates by looking at how much algae grows on my glass in a couple days haha

 

[Nathan0369]

Are you using the same vial each time? If it's a different vial, the glass is thinner in one.

 

[TRPlacek]

Are you using the same vial each time? If it's a different vial, the glass is thinner in one.

Same vial

 

[justingraham]

How do u use the same vial if I rember correctly doesn't it shut off after two mins but I have to shake the vial for two mins?

 

[TRPlacek]

How do u use the same vial if I rember correctly doesn't it shut off after two mins but I have to shake the vial for two mins?

It shuts off after 3 minutes. After pouring reagent and mixing I still have about 30 sec before it shuts off

 

[saltyhog]

Do you hold the button until the 3 minute countdown starts (after adding the reagent and mixing). Mine have never been that variable. Always orient the vial the same way each step. I use the 10ml marker to aid in doing that.

 

[justingraham]

Yea every time I did it it **** off so I stoped using it that way. Brs used two vials in one of their videos so that's what I did. Now to comment on their accuracy I have no idea I find it consistant tho if I do the same steps exactly every time but I wouldn't know the accuracy. When I send in my triton test I plan to do every test to see how acurate everything is

 

[TRPlacek]

Do you hold the button until the 3 minute countdown starts (after adding the reagent and mixing). Mine have never been that variable. Always orient the vial the same way each step. I use the 10ml marker to aid in doing that.

Yes I do.
I do it the same every time. Rinse vial with tank water and fill to line. Dry off the vial with my shirt and use an eye glass cloth to make sure vial is clean and clear. I make sure there are no bubbles after mixing reagent.

 

[TRPlacek]

Yea every time I did it it **** off so I stoped using it that way. Brs used two vials in one of their videos so that's what I did. Now to comment on their accuracy I have no idea I find it consistant tho if I do the same steps exactly every time but I wouldn't know the accuracy. When I send in my triton test I plan to do every test to see how acurate everything is

I've tried it both ways with my Hannah 713 but it seemed that it would be better to use the same vial to me so that is how I've been doing it for some time.

 

[justingraham]

I would just hate to waste the regent if I ran out of time that is my thinking as anything grabs my attention so I will be doing the test then rember that I left the stove on or a funny commercial comes on and I loose track of time

 

[bif24701]

I have been using the Hannah hi713 for several months and was always getting a reading of 0.00 ppm. I also had issues with color fading on sps but just to make sure before I started dosing phosphates I purchased a Hannah ulr phosphorous checker. My first test came up 3ppb or .009 ppm. So I proceeded to dose 1 ml of neophos in my 100 gallon tank. I tested the next day same time and got 19ppb (.058 ppm) I then tested again as this didn't seem right to me and got 4ppb (.012 ppm) which seemed in line with what I dosed. However I decided to do one more test to make sure and I got a reading of 15 ppb (.045 ppm).

Which number should I be going off of? Did I possibly get some detritus in the vial on the higher readings?

I think your conversion numbers are way way off. Take a look here where my APEX Fusion converts the numbers for me.

How are you calculating the conversion?

 

[TRPlacek]

I think your conversion numbers are way way off. Take a look here where my APEX Fusion converts the numbers for me.

How are you calculating the conversion?

If you notice I'm using 3 decimal places. The readings correspond with yours. Yours are just rounded to two decimal points.

 

[Myka]

I get very consistent readings from the Phosphorus Checker. Here is a very detailed description of how I use it:

I use a syringe to fill the vial with a couple mL of tank water, shake vigorously, then empty it and shake as much water out as possible. If there are drops left near the top of the vial I will use a bit of paper towel to get them. Then I add tank water to the 10 mL mark (bottom of the water's curve). I get the reagent packet ready by flicking all the powder down into one corner, then cut off two sides, and squish it open. I clean the outside of the vial with a microfiber cloth. Then I turn on the checker, wait for "C1". Insert the vial with the "10" on the vial pointing lined up with a mark I put on the top of the checker, close lid, set the checker down. Hit the button. Wait for "C2". Add the reagent packet, cap the vial and gently tilt it side to side for 2 mins (I time it). Hold down the button on the checker until it starts the 3 min countdown. When there's about 1 min left, I turn the vial a few times, make sure there are no air bubble on the vial sides, clean the vial with the microfiber cloth again, and insert the vial into the checker, close the lid and wait for the reading. Once I get a reading I immediately take the vial to the sink and rinse it repeatedly with water that is as hot as I can stand, using my thumb to seal water inside it and shaking it vigorously. I also rinse the lid. Afterwards I rinse it in RO/DI water, and shake it out vigorously.

 

[saltyhog]

I get very consistent readings from the Phosphorus Checker. Here is a very detailed description of how I use it:

I use a syringe to fill the vial with a couple mL of tank water, shake vigorously, then empty it and shake as much water out as possible. If there are drops left near the top of the vial I will use a bit of paper towel to get them. Then I add tank water to the 10 mL mark (bottom of the water's curve). I get the reagent packet ready by flicking all the powder down into one corner, then cut off two sides, and squish it open. I clean the outside of the vial with a microfiber cloth. Then I turn on the checker, wait for "C1". Insert the vial with the "10" on the vial pointing lined up with a mark I put on the top of the checker, close lid, set the checker down. Hit the button. Wait for "C2". Add the reagent packet, cap the vial and gently tilt it side to side for 2 mins (I time it). Hold down the button on the checker until it starts the 3 min countdown. When there's about 1 min left, I turn the vial a few times, make sure there are no air bubble on the vial sides, clean the vial with the microfiber cloth again, and insert the vial into the checker, close the lid and wait for the reading. Once I get a reading I immediately take the vial to the sink and rinse it repeatedly with water that is as hot as I can stand, using my thumb to seal water inside it and shaking it vigorously. I also rinse the lid. Afterwards I rinse it in RO/DI water, and shake it out vigorously.

Almost exactly my procedure. The only thing I do different is make sure all bubbles are out of the vial before I put it in the checker so I don't disturb the vial right before the reading is taken. My reasoning for that is the 3 minute countdown allows any precipitate/undisolved reagent to settle to the bottom of the vial so it isn't affecting the photometer.