Hanna Alk vs. Salifert

[hogfanreefer]

I've been testing with Salifert for Alk since I set up my tank. After reading the reviews and getting comfortable with the Hanna Phosphate checker I purchased an Alk checker.

I got it today and checked my Alk at 143 (8.0 dKh). I then checked with Salifert and got between 8.3 and 8.5 (0.45 ml). I know that either number is ok as long as stability is there. My worry is I've read that the Hanna is usually .7 to .8 dKh too high. Doesn't jive with my Salifert test but I don't know what to believe.

Which one do I believe?

[disc1]

Those answers are within normal error. Are the corals happy? Then just pick one and go for stability at that number. Flip a coin if you want to. The "real" answer is likely somewhere in between. If you want "real" answers, then go spend a few thousand dollars and get "real" equipment. But you don't need to do that. You just get to a happy place and try to stay there. Who cares if it's 8.2 or 8.4? What's the difference?

[hogfanreefer]

Thanks David, understood. My concern was reading that the Hanna is usually 0.7 or so high, which would mean my Salifert numbers I've been going by were wrong and I'm really around 7.3. That number wouldn't give me much wiggle room.

Maybe what I read was bogus, as you said these numbers are within margin of error. Since everything looks happy I'll just maintain the status quo.

[disc1]

Where you get the 0.7 dkH thing? I've heard that those things are terribly inaccurate, but I've always heard that readings are sort of all over the place. I've never heard the 0.7 number but then again I've never really looked.

If it were true that every alk checker read exactly off by that much then it seems like Hanna would just program the thing to read 0.7 dkH higher and the thing would be accurate.

I think you're overshooting the precision you need. When you are deciding what to wear out, do you need the temperature to three decimal places? No, even if you just get to within ten degrees you are going to pick the right clothes. Sometimes the temperature matters to three decimals, but not there. The same with this alkalinity thing. You know you're in the right ballpark, if the corals are happy then keep it there. Knowing the exact number down to some level of precision that is impossible with hobby grade equipment is not only unnecessary, but it will drive you mad very quickly.

Really, I don't care if my kit tells me that my alkalinity is QX, as long as my corals are happy and I can maintain QX by that kit I'm good to go.

[disc1]

This may make better sense. In real science we would never ever report a measured number like 8.5 dkH. With any measurement there is some level of error and we would always report that with the number. So in the case of the alk number coming from the Hanna we might say something like 8.5 +/- 1.0 dkH. When you put that plus / minus on there, those numbers stop looking so different.

[blanden.adam]

People speak very highly of the Hannah Alk checker (alk and phosphate are good, the calcium is apparently terrible), although I have heard reports it reads a shade higher than the titration based test kits in some cases. I've also heard that they don't. I don't know which one is actually true, but the titration kits and the colorimeter are probably accurate enough, and as David said, keeping it stable is the more important thing. I wouldn't worry about it, particularly because you checked it yourself.

[thegrun]

I started using a Hanna Checker for alkalinity about a year ago but since I had left over Red Sea and Salifert alkalinity test kits I've been double checking the Hanna versus Red Sea and Salifert and all three read very close to one another. From my limited testing the Red Sea seems to usually (but not always) read between 0.1 and 0.2 higher than the Hanna and Salifert results. The Salifert usually matches or is at most 0.1 higher than the Hanna. To me the Red Sea and Salifert test kits are easier to use and with the results all so close I may end up switching back when I exhaust my current stock of Hanna regents.

[heritage]

I've tested my Hanna against my seachem kit and was always within a .2 variance.
I think it's pretty accurate, but at the price point and having to order refills on line I'm going to stick with Red Sea.

[tmz]

I use the checker; it crosschecks reasonably well with the Salifert test. I agree the Salifert test is easier to perform for me . The digital readouts from the checker are nice to my old eyes though.

[dkeller_nc]

Thanks David, understood. My concern was reading that the Hanna is usually 0.7 or so high, which would mean my Salifert numbers I've been going by were wrong and I'm really around 7.3. That number wouldn't give me much wiggle room.

Maybe what I read was bogus, as you said these numbers are within margin of error. Since everything looks happy I'll just maintain the status quo.

David and other posters are right that you don't need a lot of precision, just stability. I run one of my tanks at about 10 dKH, the other at about 7.5 dKH, both have "happy corals".

But - if you're curious and want to diagnose the discrepancy, have you tried using the alkalinity standard that Salifert provides with their test? The intent of that standard is to train your eyes about how far to take the color change. There's a good bit of difference between going from the original green to the bluish/purple color and from the original green to the pink color.

[hogfanreefer]

Another good idea dkeller.

I got out my Salifert control solution that's supposed to be 6.7 dKh. Tested with both the Hanna and the Salifert.

6.9 with Salifert
5.9 with Hanna

Either test would probably be acceptable to follow alkalinity for the reasons disc1 clearly stated (the Hanna results are very repeatable). However, all things considered I think I'll go back to the Salifert.

[dkeller_nc]

Yeah, to be honest I don't see the point of using a meter to test alkalinity. The indicator is strongly colored, and with the Salifert test it's an obvious, night and day change, and their reverse-reading syringes and test results charts make determining the alkalinity a no-math breeze. And if you know about what your alkalinity is in the first place, you can just add 80% of that before doing drop-wise additions, so the test is really quick.

Having said that, the Hanna checker might really be a life-saver for someone that's partially or completely colorblind.

[xtlosx]

Hate to revive an old thread here, but I have been using Salifert for Alk\Calc and recently upgraded my alk to Hanna since the phosphate meter has been awesome. So my Hanna is giving me an Alk reading of 7.5 while the Salifert is reading 8.6.

The biggest problem for me and the reason I went Hanna on the Alk vs Salifert long term is the color change from the purple to "pink". I can never in my mind get to a reasonable color change and feel comfortable. I figured digital readout was much better approach.

One question regarding Hanna Alk. When you are using the syringe to get reagent, Do you use the bottom tick of the syringe, and the top tick, or do you just suck up enough to get to the top tick and then have some in the bottom part of the syringe? Apologies if my question doesn't make sense.

[bertoni]

What is the syringe step supposed to do? Are you doing a titration, or just measuring a quantity. I assume it's a quantity. If so, just making sure that the plunger moves the appropriate amount is fine.

[xtlosx]

Ya know, I think I might just be a dumb@ss... With Salifert, I just make sure the plunger hits the appropriate number and there is always some liquid in the bottom most part of the syringe. With the Hanna kits, I have made sure the liquid is between the two tick marks with nothing in the skinny syringe part.... Sorry, this is something difficult to describe, especially on Saturday evening :-)

Bertoni, I feel like I owe you a beer for every time you help me. Thank you!!

[Reefvet]

So my Hanna is giving me an Alk reading of 7.5 while the Salifert is reading 8.6.

The biggest problem for me and the reason I went Hanna on the Alk vs Salifert long term is the color change from the purple to "pink". I can never in my mind get to a reasonable color change and feel comfortable. I figured digital readout was much better approach.


I recently bough the Hanna digital because I got tired of trying to determine when the Red Sea Pro alk test had really completed the color change.

The Hanna is giving me 7.5 dKH and the Red Sea 8.4. Both are consistent and I much prefer the Hanna digital even if the reagents are 3 times the money.

I don't miss the subjectivity of the Red Sea kit and either value is fine with me because everything is growing and looking healthy.

[xtlosx]

I recently bough the Hanna digital because I got tired of trying to determine when the Red Sea Pro alk test had really completed the color change.

The Hanna is giving me 7.5 dKH and the Red Sea 8.4. Both are consistent and I much prefer the Hanna digital even if the reagents are 3 times the money.

I don't miss the subjectivity of the Red Sea kit and either value is fine with me because everything is growing and looking healthy.

So we're almost in the same boat here eh? Sounds like we are almost spot on. Things are doing very well, but I'm a very exact person and it would just be nice to know exactly wth the Alk level is :-) Hanna has been VERY consistent over the days, so I guess that's my solace here.

[Dapg8gt]

Ya know, I think I might just be a dumb@ss... With Salifert, I just make sure the plunger hits the appropriate number and there is always some liquid in the bottom most part of the syringe. With the Hanna kits, I have made sure the liquid is between the two tick marks with nothing in the skinny syringe part.... Sorry, this is something difficult to describe, especially on Saturday evening :-)

Bertoni, I feel like I owe you a beer for every time you help me. Thank you!!
You are doing it correctly with the Hanna if I'm reading your post right. You are getting 1ml of reagent in the tip only as needed for the test. If you filled the tip + the syringe you would have 2ml fwiw.

And if your readings are a whole dkh off I would just use the Salifert and cross check it with the standard it comes with and go from there..

I totally agree that initially I was all jazzed about the Hanna meter for the alk but honestly I can complete the Salifert faster and easier and I get to use the entire bottle of reagent.. I always seem to have to waste the last few tests of the Hanna alk reagent because it has a bunch of chunks in it that won't dissolve that do actually affect the outcome rqndomly by sometimes .5 dkh +/- or so and in my sps tank I will actually adjust for that as I think it's needed to keep on top of consumption or doubt the readings and use double the amount by retesting.

So long story short I like Salifert better than Hanna.. Cheaper, easier and seems to be consistent batch to batch, not so much with the Hanna reagent ime.

[Reefvet]

So we're almost in the same boat here eh? Sounds like we are almost spot on. Things are doing very well, but I'm a very exact person and it would just be nice to know exactly wth the Alk level is :-) Hanna has been VERY consistent over the days, so I guess that's my solace here.

Yes it would be nice to have an exact number but the reality is we'll never have one with hobbyist level kits. And has been pointed out, we really need one.

The interesting part is that if I take the value of the Red Sea Pro kit from when it might be interpreted to have changed color that makes the reading exactly the same as the Hanna. The problem is I need another couple drops to get what I feel is the complete color change. That's anoying to me. The Hanna is giving me exacly the same value each time. So I'll go with the Hanna.

[msderganc]

I use Hanna, Salifert, and Red Sea. In general, all three match (within .2-.3 dkH usually) when the tests are performed properly.

HOWEVER, and this is a big however, I've found that the Hanna becomes very inaccurate as the reagent gets down to the bottom of the container. For my latest set, I've been shaking the reagent before drawing it into the syringe, and I've had much more uniform readings.

Just to keep myself honest, I alternate test weeks between the three. If the Alk reading is off about 0.5 dkH from what I'm expecting, I pick another one and do that test.

As for standards - I found that my Salifert standard was dead on. As was suggested above, you may want to calibrate yourself on the color change with that. So if you use that standard the way you normally do, and it's 0.2dkH lower than the standard is supposed to be, just add 0.2dkH to all of your future tests. As long as you perform the test the same way in the future, it will be accurate. Hanna also has a standard for their alk checker, but I haven't been able to get a hold of one (do make sure you get their Calcium and Phosphorus standards if you have those checkers).

[xtlosx]

Thanks everyone. What's frustrating is the first couple days I used the Hanna tester, it was spot on with my Salifert. It's only been the last week or so that they have been in the basic same tight range. Wonder if I haven't shaken the bottle enough or I am getting down to the bottom possibly.

[tmz]

I cross check the hanah checker with Saifert Alk test from time to time . They are always close,ime.
When drawing in the reagent , the bottom edge of the plunger should line up with the top end of the ml scale. There is usually a bubble of air there that accounts for the reagent in the tip of the syringe.

[GroktheCube]

I've found my Hanna checker to always be within .2 dkh of other tests, EXCEPT when I get to the very bottom of the reagent bottle.

[Dapg8gt]

I've found my Hanna checker to always be within .2 dkh of other tests, EXCEPT when I get to the very bottom of the reagent bottle.
This is one of the things I really dislike about it.. You don't really get 25 of the same tests per bottle the last ones can vary quite a bit so I end up just tossing the last 5 or so tests after it lays around for months because I opened new ones..

[bertoni]

Is this a liquid reagent?

[xtlosx]

Is this a liquid reagent?

Yes it is. They are cheap enough to buy a bunch of them, so I'm not worried ab out wasting a test or two.

[bertoni]

Okay, liquid reagents do tend to have problem, especially with water evaporating.