Hannah Alkalinity Refill inaccurate.

[Terry Brown]

I am wondering if anyone has seen this? I am using the Hannah Alkalinity test kit. I get my refills from Bulk Reef supply.

My alkalinity runs 9.1. Saturday, I open a new refill and tested. The Hannah with the new refill tested at 8.1. So I pulled out the Salifert test and it tested at 9.2.

I also had some left over Hannah regent and tested again. It read 9.1

I am wondering if there are some bad batches of Hannah refills?

The lot number is 7529 Exp 12/2019

 

[Stickboy15]

Mines been reading high lately I normally run mine 9.4 and I added about 15 corals majority being sps and a clam Saturday expecting to see a drop and it’s been testing 9.8-10.0?

 

[Bayareareefer18]

Since receiving my hannah I had been solely using that to test ALK. Recently ran out of my solution so pulled out the red sea. Always had a tough time getting an exact number with red sea but can get a decent idea. With the Hannah I had been testing my ALK in the 8 range however with the red sea it gave me a reading of 9

 

[Terry Brown]

I am worried about the consistency of Hannah's reagents. I tested my old refill against the new with a reading of 9.1 vs. 8.1. That is a large margin of error.

 

[madweazl]

I've gone through four or five refills now and haven't had any significant variation.

 

[wesman42]

I'd voice your concern with the company!! They may just need to be notified if it's a bad batch.

 

[Potatohead]

I've gone through four or five refills now and haven't had any significant variation.

I've been through about ten of them and same for me, pretty consistent. The only thing I notice is the last 3-4 tests per reagent tend to read a bit high, I don't know why. But the reagent is 30ml and Hanna says they are good for 25 tests @ 1ml each, so maybe I shouldn't be using it that long in the first place.

 

[TheHarold]

Thats why the alk calibration/confirmation sample is critical. VERY well worth the $20!!!

I would probably contact Hanna first with the batch information if I had a bad reagent, thats not BRS's fault.

https://www.bulkreefsupply.com/hi772-11-alkalinity-dkh-calibration-check-set.html

 

[TheHarold]

I've been through about ten of them and same for me, pretty consistent. The only thing I notice is the last 3-4 tests per reagent tend to read a bit high, I don't know why. But the reagent is 30ml and Hanna says they are good for 25 tests @ 1ml each, so maybe I shouldn't be using it that long in the first place.

Evaporation I believe. Keep those lids on tight!

 

[Justfebreezeit]

I actually just opened a new bottle of it and had the same thing happen. exactly 1 dkh lower. I also used a new cuvette and did a water change between daily testing so I chalked it up to other changes as well.

I won't mind so much as long as the whole bottle tests 1 dkh lower but its still anoyying.

edit: mine is lot 7522 with a 11/2019 exp

 

[TheHarold]

Any testing device without a "standard" to compare it to is useless. Get the dkh calibration set.

 

[cracker]

Iv'e had the same issues. with readings that don't make sense. I also find flakes floating around in the reagent . I wouldn't mind contacting Hanna about this.
As for differing readings between kits. The other kits, redsea,selifert have always been higher. However I don't do well with matching the color changes . I refuse to go down that 'which kit is right" rabbit hole. so stick with the Hanna.

 

[Bayareareefer18]

Iv'e had the same issues. with readings that don't make sense. I also find flakes floating around in the reagent . I wouldn't mind contacting Hanna about this.
As for differing readings between kits. The other kits, redsea,selifert have always been higher. However I don't do well with matching the color changes . I refuse to go down that 'which kit is right" rabbit hole. so stick with the Hanna.

It's a shame there isn't a way to change the indicator color of ALK test kits. I find it so difficult to see that color change from blue to green and is it "enough" green or slight change, etc

So much easier reading the red to blue of cal and mag or even like a pool test kit that test alk from green to clear...

 

[madweazl]

Iv'e had the same issues. with readings that don't make sense. I also find flakes floating around in the reagent . I wouldn't mind contacting Hanna about this...

I contacted Hanna regarding the floaties a year or two ago and they stated it wouldn't affect the reading. They also offered to ship a new reagent bottle if I was concerned about it.

 

[scardall]

Any testing device without a "standard" to compare it to is useless. Get the dkh calibration set.

I have a Hanna dkh cal. set and confirmed the meter is in cal. In addition I have an ELOS kit and it is close as I'm looking for a color change. So it is possible to be off .5dkh . I also had a salifert test done and it read 1-1.5dkh higher.

 

[Terry Brown]

Cracker, I see stuff floating around in my reagent as well. I agree on not going down the rabbit hole trying different test kits.
I am looking for a stable alkalinity reading more than an exact number.

TheHarlold, so are you calibrating your Hannah Checker every time you get new regent? Seems over-kill to me, and kind of negates the whole reason I bought Hannah which is for easy of use and consistency in testing (ie less room for error by taking the human element out of the test)

 

[cracker]

Well said @Terry Brown !

 

[TheHarold]

Cracker, I see stuff floating around in my reagent as well. I agree on not going down the rabbit hole trying different test kits.
I am looking for a stable alkalinity reading more than an exact number.

TheHarlold, so are you calibrating your Hannah Checker every time you get new regent? Seems over-kill to me, and kind of negates the whole reason I bought Hannah which is for easy of use and consistency in testing (ie less room for error by taking the human element out of the test)

Perhaps you misunderstood what I meant by the check solution. The Hanna checker does not “change” it’s calibration according to what it reads from the solution. It is just way to verify that it is reeading accurately: properly zerod, etc.

 

[DivingTheWorld]

My meter is in calibration, but I've been noticing something similar, reading 1 dkh lower. I'll have to check my reagent batch when I get home. I did buy them from BRS.

 

[Terry Brown]

I just contacted Hanna Instruments and they said in the past there was some issue, but they have had no reports of bad lot numbers. To be honest they did not seem to care that I had a bad refill kit. I also informed them that some of you (on Reef2Reef) have seen similar issues. I tried to give them the lot number but they did not want it. They just said if it happens again let them know.