Bad Hanna phosphate kit?

[Zacktosterone]

I did a test yesterday and my Phosphate level was 0.12. I did another one today and it said 0.02 so I did five more tests and they all say 0.00


Is there any way I can test this to make sure it's right? I used the calibrate test kit after that (which you can only use one time) and it read 0.00

 

[tkeracer619]

Which test kit do you have?

 

[slief]

I did a test yesterday and my Phosphate level was 0.12. I did another one today and it said 0.02 so I did five more tests and they all say 0.00


Is there any way I can test this to make sure it's right? I used the calibrate test kit after that (which you can only use one time) and it read 0.00

Which test kit do you have?

+1

The HI713 phosphate tester is said to have .04+/- PPM margin of error. I've seen water that was .10 on my HI736 consistently read 0 with the 713, If you have the 713, I am not sureprised you are getting those numbers. The 713 isn't ideal for our range.

That said, Hanna has had some bad regent batches over the years so you might as well contact them and let them know what you are seeing. They may just send you some new regemts. They are pretty good that way when it comes to those kinds of issues.

 

[Zacktosterone]

I have the 713... I didn't grab the ultra low because brs his told me not to

 

[slief]

I have the 713... I didn't grab the ultra low because brs his told me not to

That was not a good suggestion on their part and this is also where a bit of research can come in handy. The Ultra Low HI736 is the true marine tester that is designed for our use and is the most accurate for ultra low range Po4 which is the level we target. My guess is whoever made the recommendation isn't familiar enough with the Hanna testers or was misinformed. This is also why the HI736 is noted as a Marine tester for Salt Water Aquariums and the HI713 is not.

HI713: Not that it makes no mention of Marine or salt water aquariums let alone salt water:
http://shop.hannainst.com/hi713-phosphate-lr.html

HI736. Note that it says: "For Salt Water Aquariums" because its the most suitable for our test range and is designed for salt water.
http://shop.hannainst.com/hi736-phosphorus-ulr.html

 

[Zacktosterone]

That's irritating. You're the first person to tell me this. I've read other forms as well and people say its the best one. So was I supposed to know that my meter was incorrect

 

[EllisJuan]

The 736 is definitely the one you want. I would contact whoever sold it to you and let them know you feel misled. Maybe they will exchange it for you.

 

[slief]

That's irritating. You're the first person to tell me this. I've read other forms as well and people say its the best one. So was I supposed to know that my meter was incorrect

I understand your frustration... Sorry to be the barer of bad news. There have been dozens of threads here where I shared similar information. The 713 just isn't accurate in our range and Hanna is clearly confirming that by differentiating the two with the nomenclature that have on the HI736.

Sadly, people including many of the resellers are misinformed. People see the words phosphate tester and take that for granted. They don't realize that the phosphorus tester is more accurate and is designed for our range of testing. The see low range and don't realize that our target range is Ultra Low Range. There is some math involved in converting the HI736 results for Phosphorus PPB into Phosphate PPM but in the end, you get much more accurate results in our target range. In fact, I can pretty much guarantee that any true Po4 reading of .05 or less will result in a 0 reading with the HI713. Anything below .10 will result in numbers that are way off and in most cases a result anywhere from .04 to 0. More often than not, the latter. Bottom line, the lower the actual Po4 levels, the less accurate the 713 will be. In fresh water, the results may be different.

If you do get the HI736 which is what I would do and in fact what I use, you take the test results and multiply it by 3.066. This converts Phosphorus to Phosphate in parts per billion (that's the resolution of the 736). Then you divide that number by 1000 to convert to parts per million which is the traditional reading we refer to when testing for Po4.