Which testing kit do I trust?

[Hanna Instruments]

I'm in a similar boat. Red Sea .04 Phosphates. Hanna .91. Thats a huge difference.

Red Sea: 4 Nitrates. Salifert ad API 30.

If you are using our HI713 Low Range Phosphate Checker the measure of uncertainty is ±0.04 ppm ±4% of reading.
If you are using our HI736 ULR Marine Phosphorus Checker the measure of uncertainty ±5 ppb ±5% of reading

 

[Catfish2]

How are you maintaining calcium and alkalinity? If your using kalk, a calcium reactor or equal parts 2 part, you may not have to keep frequently testing calc or mag. If your alk is steady, they both should be inline with your last test.

I'm dosing 2 part. I check calcium weekly and mag when I feel like it, maybe monthly.

I was wondering if you think it's important to check ca and mag at the same time of the day. I never thought it was important to check them at the same time of day, but I never really thought about it before.

 

[SashimiTurtle]

My Red Sea Pro and Hanna dKH checker have always been very close to each other. Usually within 0.1dKH.

 

[SashimiTurtle]

My Red Sea Pro and Hanna dKH checker have always been very close to each other. Usually within 0.1dKH.

 

[40B Knasty]

ELOS is the only test kit I trust. Easy to read, to use, and reagents are NIST certified.

 

[Hanna Instruments]

ELOS is the only test kit I trust. Easy to read, to use, and reagents are NIST certified.

Thanks for your input! Is there a particular reason you find NIST certification valuable?

Hanna Instruments is an ISO (International Organization for Standardization) 9001 certified company in the scope of manufacturing, testing, packaging, storage of proprietary brands for analytical measuring instruments and sensors, monitoring and controlling inline-process equipment, chemical reagents and standard calibration solutions, as well as related accessories and spare parts.

https://www.iso.org/iso-9001-quality-management.html

 

[40B Knasty]

Thanks for your input! Is there a particular reason you find NIST certification valuable?

Hanna Instruments is an ISO (International Organization for Standardization) 9001 certified company in the scope of manufacturing, testing, packaging, storage of proprietary brands for analytical measuring instruments and sensors, monitoring and controlling inline-process equipment, chemical reagents and standard calibration solutions, as well as related accessories and spare parts.

https://www.iso.org/iso-9001-quality-management.html

Yes. The reagents are the only important part of the test kit. 2nd would be how to use them together. I do not need all the bells, whistles, and a digital screen to give me an inaccurate reading if a company can not get step one right. I have seen all the videos showing me what not to buy. Even if they are a ISO 9001 Certified Co. No offense. I just know where this is going and would like a end it here. The thread was for what test kit do you use?

 

[justingraham]

I use Hannah
But what I do is if the regent is about to expire (and I do not have any of the same lot stockpiled up) I run two test one with the old regent and then one with the new. I do this for three test. I have found that when you switch lots u will get diffent results but if test like this u know the diffence. (This is why I try to buy all the same lots)

Hannah I'm sure will defend themselves but this is what I have come across and I test alk everyday. The difference is always within their margin of five but i have yet to come across one lot matching another

 

[Hanna Instruments]

Yes. The reagents are the only important part of the test kit. 2nd would be how to use them together. I do not need all the bells, whistles, and a digital screen to give me an inaccurate reading if a company can not get step one right. I have seen all the videos showing me what not to buy. Even if they are a ISO 9001 Certified Co. No offense. I just know where this is going and would like a end it here. The thread was for what test kit do you use?

We replied to this thread as the original poster was experiencing discrepancies between our product and another test kit. We value our customers and hope to provide the best testing experience and support possible.

We appreciate your feedback, if you ever need support or have questions please contact us at 401-765-7500 Monday-Friday 8:30am-5pm (EST) or [email protected].

I use Hannah
But what I do is if the regent is about to expire (and I do not have any of the same lot stockpiled up) I run two test one with the old regent and then one with the new. I do this for three test. I have found that when you switch lots u will get diffent results but if test like this u know the diffence. (This is why I try to buy all the same lots)

Hannah I'm sure will defend themselves but this is what I have come across and I test alk everyday. The difference is always within their margin of five but i have yet to come across one lot matching another

Thank you for using our products!

 

[Ashish Patel]

I use Hanna and Redsea... I find the redsea Alk test kit faster to do on a daily basis that the Hanna. .. No need to worry about calibrating, wiping the glass, or using the long needle. In terms of accuracy I would go with Hanna all day.. With Redsea and saliferts their is too much room for error and when your dosing its nice to have more accuracy to the .01 range. Yesterday my redsea measured at 9.0 dkh and my hanna was at 8.5DKH. Tonight if they are different I know something is off but generally they are .5 DKH off anyways.

 

[Jlentz]

I have a phosphate and alk Hanna test. I've only used the alk test twice since the Red Sea alk test is much easier and faster. I'd love to get a Hanna nitrate tester if one is available.

 

[Catfish2]

I think the question in my original post has got a little lost in all these responses. I truely appreciate everyone's input, but I was not asking a general question about which test kit to trust our which is better or what are the merits of each method.

I was asking: in my specific case, where hanna and red sea matched almost perfectly one day, but then the next day with a new hanna reagent the hanna read significantly lower, what would you do? Furthermore, subsequent hanna reagents have read consistent with each other, which is abut 1 dkh lower than red sea. I'm either at 8 or 9 dkh, neither one is bad, so im not too worried, but it did raise the question.

I guess since hanna is on here, I can ask them directly. ...
@Hanna Instruments,
What would you do in my case? On 7/29 my hanna checker read 8.8. The next day with no significant changes or dosing, the new reagent read 7.6 and on a retest read a consistent at 7.5. Since then, I have raised my alk by dosing 2 part. Hanna read it at 8.1 and red sea at 9.0-9.2. Which number would you take.

At this point, I've settled on not worrying about the exact number and instead looking for trends up or down.

 

[don74136]

I use Red Sea, Hanna Checker, and eXact iDip. They all give different results but are close enough to each other that I might just stick with two of them: the eXact iDip and the...?

 

[Mindi]

I use the Hanna. I always run and fore and aft comparison when I get a new reagent bottle. My strictly anecdotal view is that the Alkalinity reagent which is nearly expired gives a higher reading than the new reagent...like maybe 3.8meq/l compared to 3.5meq/l.... so I reckon the reagent shifts over time a little towards higher readings. ...but I doubt it matters.

 

[Biznizface]

Fauna Marin DKH test kit.

One regeant. Clear colour change from blue to orange.

The daddy imo.

 

[Sense of nature]

Lamotte test kits are top notch

 

[madweazl]

Tested a fresh batch of Reef Crystals a while back and ended up with the below results. All three were fairly close but yesterday, I did have a wild reading from the Hanna checker (9.7 that shouldn't have been over 9.0). This was the last of a bottle that didn't expire for almost another year but there was only about .5ml left in the bottle after this test was done. I toss the results when I get a wild one like this but had I observed what you were getting regarding consistent results between two kits and one suddenly showed a large delta consistently, I'd toss that entire bottle of reagent IF I knew nothing contaminated the other (Red Sea) kit.

Hanna
dKH 11.65

Red Sea (changed after 11 but before 12 so guesstimated 11.5)
dKH 11.5

Salifert
dKH 11.05

 

[40B Knasty]

I think the question in my original post has got a little lost in all these responses. I truely appreciate everyone's input, but I was not asking a general question about which test kit to trust our which is better or what are the merits of each method.

I was asking: in my specific case, where hanna and red sea matched almost perfectly one day, but then the next day with a new hanna reagent the hanna read significantly lower, what would you do? Furthermore, subsequent hanna reagents have read consistent with each other, which is abut 1 dkh lower than red sea. I'm either at 8 or 9 dkh, neither one is bad, so im not too worried, but it did raise the question.

I guess since hanna is on here, I can ask them directly. ...
@Hanna Instruments,
What would you do in my case? On 7/29 my hanna checker read 8.8. The next day with no significant changes or dosing, the new reagent read 7.6 and on a retest read a consistent at 7.5. Since then, I have raised my alk by dosing 2 part. Hanna read it at 8.1 and red sea at 9.0-9.2. Which number would you take.

At this point, I've settled on not worrying about the exact number and instead looking for trends up or down.

My bad. I thought you were using the question stated for the thread in a 3rd person/hypothetical question sense.
So it basically comes down to. Well which one do you trust?
If you are asking us. We can not answer that. Just give you similar experiences or try another kit.
Which test kit have you trusted from the beginning that has gotten you this far is the one you should trust. Unless the reagents have not been stored properly, expired, moisture got on the powder, or you didn't shake/mix the bottle if the directions specifically said that.

 

[Hanna Instruments]

I think the question in my original post has got a little lost in all these responses. I truely appreciate everyone's input, but I was not asking a general question about which test kit to trust our which is better or what are the merits of each method.

I was asking: in my specific case, where hanna and red sea matched almost perfectly one day, but then the next day with a new hanna reagent the hanna read significantly lower, what would you do? Furthermore, subsequent hanna reagents have read consistent with each other, which is abut 1 dkh lower than red sea. I'm either at 8 or 9 dkh, neither one is bad, so im not too worried, but it did raise the question.

I guess since hanna is on here, I can ask them directly. ...
@Hanna Instruments,
What would you do in my case? On 7/29 my hanna checker read 8.8. The next day with no significant changes or dosing, the new reagent read 7.6 and on a retest read a consistent at 7.5. Since then, I have raised my alk by dosing 2 part. Hanna read it at 8.1 and red sea at 9.0-9.2. Which number would you take.

At this point, I've settled on not worrying about the exact number and instead looking for trends up or down.

I use Hannah
But what I do is if the regent is about to expire (and I do not have any of the same lot stockpiled up) I run two test one with the old regent and then one with the new. I do this for three test. I have found that when you switch lots u will get diffent results but if test like this u know the diffence. (This is why I try to buy all the same lots)

Hannah I'm sure will defend themselves but this is what I have come across and I test alk everyday. The difference is always within their margin of five but i have yet to come across one lot matching another

Hello, I am curious to know if you are using the same syringe and tip for different reagents? Also are your syringes clean or do they have dried reagent in the tip or syringe portion when you store them after use?

 

[Catfish2]

Hello, I am curious to know if you are using the same syringe and tip for different reagents? Also are your syringes clean or do they have dried reagent in the tip or syringe portion when you store them after use?

I used the new syringe and tip with the new bottle. I rinse the tip (inside and out) with rodi after each use and make sure it is dry before using again. There is no dried reagent in the tip or syringe. In fact no reagent even makes it into the syringe itself as the tip is large enough to hold 1ml.

 

[justingraham]

Mr or mrs Hannah person

Some times when I test the alk it takes about ten times the normal limit for the c2 to show up when it does this I start over as I think of it as a bad test. Usually when I run thru it the second time it only takes the five seconds for the c2 to show up.


My question is why does it do that? I have figured out that it's not the vial as I have 8 bottles in a rotation and it has happened to everyone of them at least once.

Thanks

Justin