Hanna Alk Checker

[Boomer]

Just up recently

Hanna Instruments' Checkers: Alkalinity and Phosphate

http://www.advancedaquarist.com/2011/8/review

Off more than that 10 % like we thought.

[DustinB]

Ouch. Have there been any tests like this on a salifert alk kit? My salifert and hanna are right in line.

[JG1]

whats the correction factor for the alk checker?

[BigKahuna]

The results with the PO4 checker are quite impressive though:

The results generated by the inexpensive Hanna Checker are remarkably close to those reported by a $3,500 spectrometer.

[maysorum]

Ouch. Have there been any tests like this on a salifert alk kit? My salifert and hanna are right in line.

I agree, my Hanna and Salifert results have been close day after day. Here's today's numbers:

ALK
hanna 7.952
salifert 8.15

CA
hanna 439
salifert 445

[Boomer]

Yes Kahuna they are more than impressive :)

[Boomer]

John

Looks like add 50 % :lol: Reading 100 ppm add 50 ppm = 150 ppm

[BrassMonkey]

Ya I noticed mine was off cause my sps tank wouldn't drop below 171 ppm. With the above correction that means my tank was actually a at 6.77dkh. I don't trust my Hanna meter.

[jimsplace]

To be fair and before we all get up in arms about the Hanna checker, why not preform the same test using say a Salifert Alk kit? I would bet the results would be the same or worst.

[HighlandReefer]

Thanks for the update Boomer. :thumbsup:

Hobby grade test kits and $50.00 meters will be a problem for some time to come. :lol:

These are the main reasons why one should shoot for the middle of the recommended ranges. :)

[disc1]

I doubt its going to be the kind of thing that a single correction factor can fix. I'm hearing way too much about water with very different all content hiving the same reading on the Hanna.

[JG1]

John

Looks like add 50 % :lol: Reading 100 ppm add 50 ppm = 150 ppm

Your kidding? :eek1:

[JG1]

Somethings not right because my salifert kit reads about 1.2dkh HIGHER than my hanna

[Psyops]

Sometimes I feal like the more I learn, to more I realize that I don't know anything.

I guess that is good news for phosphate and not so good for Alk. It might explain how some people can keep good SPS tanks with higher phos numbers on Hanna readings.

Thank you for finding that post Boomer!
Alex

[doctorgori]

Sometimes I feal like the more I learn, to more I realize that I don't know anything.

yeah, well try sifting through those "Advanced Aquarist" articles using only avg IQ and a Cleveland Public Schools edumacashun ... I gave up after trying to enunciate "tiration" ...I didn't know whether to get "excited" or get embarassed...

typically I wait for the breakdown from post like the above

[Boomer]

OK, I need sot make some clarifications here as I jumped the gun somewhat :(

First, this is not really clear;

Looks like add 50 % :lol: Reading 100 ppm add 50 ppm = 150 ppm

That is the HACH going to the Hanna. So, from the Hanna to equal the HACH it is subtract 50 % HOWEVER, at what many run their Alk at 180 ppm = 3.6 meq / l = 10 dKH it is more like subtract 25% of Hanna reading. At the HACH 180 and the HANNA 240 mark. Hanna 240 x 25 % = 60 and 240 - 60 = 180.

But there is more here

Dana's link on Alk is not to Randy's link on Alk.

What is Alkalinity
http://www.advancedaquarist.com/2002/2/chemistry

From it:

The precise endpoint of a total alkalinity titration isn't always the same pH, but rather depends a bit on the nature of the sample (both its ionic strength and its alkalinity). For normal seawater, this endpoint is about pH = 4.2. In freshwater it depends strongly on the alkalinity, with an endpoint of pH = 4.5 for an alkalinity of 2.2 meq/L, and pH = 5.2 for an alkalinity of 0.1 meq/L.


Well, the Hach kit was designed for use in fresh water where the pKa of the bicarbonate is much higher than in seawater, and in that situation, it is appropriate. In seawater, however, it is marginal. My tank water took 3.4 meq/L to get down to pH = 5.03, and then an additional 0.4 meq/L to get down to pH 4.00. Consequently, this kit (and others with a similar dye mix) may be missing out on 10% of the alkalinity simply because it isn't titrating low enough. This difference obviously isn't significant to most reef keepers, but is something to keep in mind when doing such things as comparing test kits to standards (in seawater) or to each other.

So now we need to add 10 % to that HACH reading of 180 = 198

Now the Hanna is reading 18 % to high.

HACH = 198

Hanna = 240

240 x 18 % = 43 and 240 - 43 = 198

So, the correction error for the Hanna to get a better true value is :

Hanna - 18 % of reading at ~normal pH and Alk.

This is MY fault for NOT thoroughly reading th article and all that it does and did not involve. I will let Danna know.

Sorry guys :)

[ksed]

Good catch Boomer

Thanks for the clarification.

[JG1]

Are we now sure that hanna reads 18% high? This is across the board for all the alk checkers and not an individual one?

[JG1]

So if we're aiming for a 9-10dkh we should shoot for a 196-218 on the Hanna?

[Boomer]

JG

There is no absolute certainty here for me unless this checker was sent to Millero's labs, as to how far it is really off. Same for the Salifert or any other kit used for Alk. Alk testing is NOT an easy thing in Seawater. And all kit and metes are based on FW. The Salifert is suppose to be for seawater but I see issues with it also, as it reads even higher than the Hanna,at least form posts here. We CAN NOT go by what companies say.

This is across the board for all the alk checkers and not an individual one?

Just this one by Hanna

9-10dkh we should shoot for a 196-218 on the Hanna?

Yes, close enough.

Our issue is any of these kits or meters need to be sent to a REAL seawater expert for testing, such as Dr. Frank Millero, the leading expert on these issues.

So, to all guys here it looks like Alk is still a shot in the dark. Maybe Dana will run some new tests. I have PM him.

[Bryan]

I and others have experienced issues with the reagents possibly going bad once open which seems to dramatically affect the test results.

http://www.reefcentral.com/forums/showthread.php?t=2057033

[Psyops]

Thanks Boomer for the clarification. At the end of the day if your tank inhabitants are looking good despite the higher readings so be it.

Ironically my tank is looking better overall with a Hanna Phos reading of 0.07 ppm instead of my usual 0-0.02 readings.

doctorgori: I thing you and I will be good cyber friends.

[kendo]

So I just tested my alk using both the api test kit and the hanna alk checker, on the api kit I got a reading of 8dkh and on the hanna I got a reading of 145 or 8.1dkh .Could this be right or is my alk lower than 8dkh?
Thanks.

[Bryan]

I have always found the API to be very accurate and consistent so think youa re in the ballpark. My API and hanna are very close to each other.

[Boomer]

Guys I spent allot of time with Habib from Salifert and we are not out of the water yet, so will reply here more soon. I l also talked to Chris Jury about it. This whole Hanna and test done by my friend Dana seems to be a big mess. It appears the Salifert is right on and does read higher than the Hanna and is suppsoe to. That means the Hanna is more accurate than the HACH test done in the article. In Alk testing there is a serious issue between CO2 in FW and CO2 in SW. Also, the titration end point is not the same at high Alk as it is low Alk. I looked at Millero Labs (the only place to test a Alk kit for seawater) data sheets on the testing of the it and it is +/- 0.1 dKH within NSW on his reagents. I will try to get Habib to reply to this thread. He is thinking of doing a full blown article for Advanced Aquarist to clear up all this Alk mess we have always had to deal with. I have said for years the Sailfert is the best Alk test and it now seems to being proved me right again but have had my doubts from posted Salifert values and Dana's article. I too have been led astray.

This is who Dr. Frank Millero is

http://cdiac.ornl.gov/oceans/

http://www.rsmas.miami.edu/people/faculty-index/?p=frank-millero

http://www.amazon.com/Chemical-Oceanography-Frank-J-Millero/dp/0849384230

[bertoni]

Interesting. I hope the article gets published!

[Sport507]

This thread has been on my mind for sometime. I just tested the alk. in my DT and here is what I found. Test with Hanna tester was 6.8 dKH my test with the Salifert was 6.7 dKH. So I feel relaxed that the one I have is a good one.

[redhanded77]

I also just got my hanna alk tester. I tested against salifert and results were close.
salifert - 8.5dkh
hanna - 145ppm

[MammothReefer]

Hmm, interesting I always found my salifert tests to very between kits, and a few years back ran into a number of issues with them misreading. I ended up switching to ELOS which worked for a while, then I found a discrepancy between 2 kits (I always do a test w/the new kit and the old before I make the switch). So I switched back to Salifert where I found a HUGE difference between Elos & Salifert. My Salifert kit was reading 2dkh higher then my elos. Finally I figured I would try the Hanna, hoping it would at least leave out any guess work done by my eye. I found my hanna to read slightly less then my salifert. Now I'm just kinda at a loss, but I shoot for 8-8.5dkh hoping that if I'm off by +/- 1.5 I'm "ok". As long as I get constant results. I'm a happy camper. It's the best I can ask for I guess? Unfortunately.. I've spent the past month trying to re-dial in my dosers as my alk is doing something weird things. I do hope it's not the tester..

[theturk]

I purchased a Hanna ALK test meter and got test results of 169 which I think means 9.464 (which is 169 * .056) -- did I do that correctly? Is this a good ALK number or is it a bit low? Thanks

[Sport507]

I purchased a Hanna ALK test meter and got test results of 169 which I think means 9.464 (which is 169 * .056) -- did I do that correctly? Is this a good ALK number or is it a bit low? Thanks

Yes you did that right. 169PPM x .056 = 9.464dKH. The range for Alk is 7-11dKH. I like to keep mine 8-10 so 9.4 is not low, about right IMO.

[007Bond]

Hi All, I get my new Hanna alk. checker tomorrow, are we saying I should also get a Salifert kit just to cross ck.the Hanna?

[DustinB]

From what I get out of what is being discussed, it would be a good idea. As long as you get the Salifert from a good source to ensure it's far from expiration.

My salifert and hanna read very close.

[007Bond]

From what I get out of what is being discussed, it would be a good idea. As long as you get the Salifert from a good source to ensure it's far from expiration.

My salifert and hanna read very close.

DB. That is how it seems to be coming across on the thread.I would think we should be able to use what ever the decided multiplier +/- for the Hanna is, to come up with a Correct alk. #. May be a cross ck is ok every so often, and if the Hanna gives readings that are consistent, with out major swings, seems the Hanna would be fine without having to depend on how my eyes are working from one day to the next. I guess if it were easy we would find another pastime.

[DustinB]

As long as the hanna is close and consistent I imagine that would be good enough for all intensive purposes. Consistency would be the main thing.

[007Bond]

My Hanna tester came today. Question,- with the tip on the 1mL syringe when I pull back the plunger the reagent dose not enter the syringe when the plunger is pulled back as far as it can go without coming out of the syringe. There is no marking on the tip so I don't know if I have 1mL or not? also the regent seems to start to drain from the syringe on its own immediately. Am I doing something wrong?

[DustinB]

No, you got a bad syringe, the one that came with my calcium kit is already bad after 2 uses. Call Hanna.

[007Bond]

No, you got a bad syringe, the one that came with my calcium kit is already bad after 2 uses. Call Hanna.

Thanks DB., I thought as much.

[outssider]

the tip may not be fitting on tightly enough. (leakage) Mine did the same until i put a wire tie around the end where it goes on to the syringe, makes it fit much tighter. pull the syringe up to where you would normally to get 1ml. there will be 1ml in the tip.

[007Bond]

Ok I have the tip fitting tight, and the reagent is no longer leaking back out on its own, but the reagent still only reaches the top of the tip where it attaches to the syringe and dose not enter the syringe. Is this correct or should the reagent also go into the syringe a bit? I want to make sure I'm using the correct amount of reagent

[ecomdesign]

If you start with the plunger down at 0 and pull it back to the 1ml mark you will have 1ml of fluid in the tip. The tip holds slightly more then 1ml of fluid.

[007Bond]

If you start with the plunger down at 0 and pull it back to the 1ml mark you will have 1ml of fluid in the tip. The tip holds slightly more then 1ml of fluid.

I guess where I'm confused, is the markings on the syringe start with 1.0 ml when closed, and go up to 0.1when open. When I pull the plunger full back to 0.1 the regent fills the tip but dose not enter the syringe at all. is this correct?

[bertoni]

If the reagent doesn't enter the syringe, you need a new syringe or tip, or both.

[TandN]

Looking forward too more about these

[Mile High Reef]

Used my HI-755 for the first time last night, hoping I was successful.

I was able to draw reagent into the tip and all the way to the 1.0 ml line with the plunger pulled almost all the way out. I guess we do draw reagent just barely into the syringe itself, correct?

Got a reading of 173 * .056 = 9.688 dkh Guessing that based on the product review posted originally by Boomer, and not having compared the results with any other test kit, that it is possible that my reading is a bit high so can I safely assume that my alkalinity is around 9 or so?

Also, rinsed the syringe and tip thoroughly in RO and stored for next test, any other suggestions for having clean syringe and tip for next go?

Thanks,
P

[MammothReefer]

I don't use the tip, I just draw the regent to the 1ml line. The other day I tested it and my test matched w/salifert. I don't see the point of the tip. If you need 1ml of regent. Pull 1ml of regent.

[007Bond]

Used my HI-755 for the first time last night, hoping I was successful.

I was able to draw reagent into the tip and all the way to the 1.0 ml line with the plunger pulled almost all the way out. I guess we do draw reagent just barely into the syringe itself, correct?

Got a reading of 173 * .056 = 9.688 dkh Guessing that based on the product review posted originally by Boomer, and not having compared the results with any other test kit, that it is possible that my reading is a bit high so can I safely assume that my alkalinity is around 9 or so?

Also, rinsed the syringe and tip thoroughly in RO and stored for next test, any other suggestions for having clean syringe and tip for next go?

Thanks,
P

Sounds like your syringe is working correctly. I called Hanna about mine today and the fellow said they would send me a couple new ones. Like M. Reefer said I don't see the need for the tip, as a ml. is a ml. I also would like to here what Boomer has found out as far as how accurate the readings are? If we should use some kind of multiplier on the meter reading, to come up with a more accurate dKH.?

[Sport507]

Ok I have the tip fitting tight, and the reagent is no longer leaking back out on its own, but the reagent still only reaches the top of the tip where it attaches to the syringe and dose not enter the syringe. Is this correct or should the reagent also go into the syringe a bit? I want to make sure I'm using the correct amount of reagent


I had an old one laying around so I used water with red food coloring in it for and example of how it will look. Just always remember to push the tip very tightly on the syringe and pull the liquid very slowly from the bottle.

[007Bond]

I had an old one laying around so I used water with red food coloring in it for and example of how it will look. Just always remember to push the tip very tightly on the syringe and pull the liquid very slowly from the bottle.

Thanks Sport, That is the level I was getting. I was not sure it was correct. After talking to the Hanna CS. guy today he said that as long as you pulled the plunger back to the 0.1 mark you would be getting the 1ml. of reagent, and after a few tests I see that the reagent dose not enter the syringe. But a picture is worth a 1000 words. Thanks for your effort I'm sure it will help others also. I seen your post, that said your Hanna and Salifert tests are about the same. Have you crossed ck.ed them a few times? The Hanna seems easy to use if we know the read out is correct.

[Sport507]

Thanks Sport, That is the level I was getting. I was not sure it was correct. After talking to the Hanna CS. guy today he said that as long as you pulled the plunger back to the 0.1 mark you would be getting the 1ml. of reagent, and after a few tests I see that the reagent dose not enter the syringe. But a picture is worth a 1000 words. Thanks for your effort I'm sure it will help others also. I seen your post, that said your Hanna and Salifert tests are about the same. Have you crossed ck.ed them a few times? The Hanna seems easy to use if we know the read out is correct.

You're more than welcome, always try to illustrate/pics if possible.

Enjoy your tank and happy reefing.:beer:

[bertoni]

The purpose of the tip on the syringe is to increase the precision of the test. It can be skipped if you're not interested in all that much accuracy.

I never bothered cleaning the reagent syringes. I don't think it should be necessary, although every kit is different.

[007Bond]

Is there any further clarity on the accuracy on the Hanna checker? On Boomers last post #25 it was kind of up in the air. Do we need to use some multiplier # on the Hanna read out? Others are posting that their Salifert and Hanna have similar readings, how should we be interpreting our Hanna's?

[bertoni]

There are three Hanna models. Most people have one of the smaller checkers. The Phosphorus ULR range checker requires a multiply by three to get ppm phosphate. The other checker reads in ppm phosphate directly.

I have heard various reports as to the accuracy. Some people have gotten very good results, and if I were going to buy a test kit, I probably would get one of the ULR checkers, but I'd probably double-check it for a while with my Hach kit.

[007Bond]

I have the new small Hanna HI 755 CHECKER. I thought that what this thread was about.

[bertoni]

Sorry, I got confused about which checker we were discussing. :lol:

[007Bond]

Any new thoughts/input on the accuracy on the HI755 CHECKER vs. other test kits?

[rigleautomotive]

I actually love my hanna checkers.The first few posts really were a bit unfair and I believe boomer did clarify at some point.The fact that the hanna may be off by a certain factor say + or - 1 dkh for argument purposes and for instance,you maintain your alk at a recommended range of say 8.5 to 9.5 you are in a safe area regardless.The reason I love the hanna against any test kit under say $100 is the accuracy on repeated testing done on same sample.,when repeated tests are done on a single sample,The results are usually spot on for each test done.If several tests are done with a salifert alk kit (or similar),same sample,the results of each test will be off (and vary)by a fair amount (test kit noise,and user error i suppose).So for me,I know when my corals look there best and this correlates to 8.5dkh on the hanna.I can keep it much more stable this way by having a good constant to keep my alk tweeked with.Using a salifert kit I would get .5 to 1 dkh variance between tests when actually the alk was very stable.For me a stable way of measuring is the important factor given the instrument is somewhat accurate for our coral keeping purposes.

As far as the Phos checker.This is also a very constant way of measuring low phos levels.Again if it is off by a reasonable amount but I get consistent measurements on the same sample tested three or 4 times,I know this # is somewhat trust-able.On the contrary,if I get 4 significantly different readings from several tests done on the same sample with test kits,I find this # not trust-able.

[tfp]

so is the general consensus that the hanna alk checker reads 18% high as reported?
or does more testing need to be done.

[rigleautomotive]

so is the general consensus that the hanna alk checker reads 18% high as reported?
or does more testing need to be done.


Here are my findings with my particular hanna alk checker.Same sample checked three times with the hanna came up 7.5 dkh consistently.Same sample tested with a new salifert alk (exp 5-2015 )kit comes up at 8.3dkh,8.6dkh,and 8.0dkh with me trying very hard to decipher the color change equally.This kit was checked with the calibration fluid and was very close to the 7.3 listed on the bottle.This would point to the Hanna reading lower in this case but it may not hold true with a hach or other high end test kit.

[endlessblue]

when will they make an all in-one meter. Just add a drop and it tells you everything hmmm

[007Bond]

Here are my findings with my particular hanna alk checker.Same sample checked three times with the hanna came up 7.5 dkh consistently.Same sample tested with a new salifert alk (exp 5-2015 )kit comes up at 8.3dkh,8.6dkh,and 8.0dkh with me trying very hard to decipher the color change equally.This kit was checked with the calibration fluid and was very close to the 7.3 listed on the bottle.This would point to the Hanna reading lower in this case but it may not hold true with a hach or other high end test kit.

So your test say the Hanna reads lower than the Salifert. Or Not? which is the correct reading? My Hanna Checker reads consistently on a same sample also which is good, I would like to know, how close to a correct reading it is putting out or do we need to use some type of a multiplier to add or subtract from the meters reading? You can't beat the ease in using it!

[rigleautomotive]

So your test say the Hanna reads lower than the Salifert. Or Not? which is the correct reading? My Hanna Checker reads consistently on a same sample also which is good, I would like to know, how close to a correct reading it is putting out or do we need to use some type of a multiplier to add or subtract from the meters reading? You can't beat the ease in using it!

My tests show that the hanna reads lower then a new salifert alk kit.I tried this on two separate alk kits and both tested and showed a higher dkh value of approx .8 dkh compared to MY hanna checker.Again,keeping the alk in your tank in the middle of the acceptable range will give you the comfort zone you need and using the hanna checker to keep it stable(long term) is my weapon of choice.

[Rogger Castells]

I actually love my hanna checkers.The first few posts really were a bit unfair and I believe boomer did clarify at some point.The fact that the hanna may be off by a certain factor say + or - 1 dkh for argument purposes and for instance,you maintain your alk at a recommended range of say 8.5 to 9.5 you are in a safe area regardless.The reason I love the hanna against any test kit under say $100 is the accuracy on repeated testing done on same sample.,when repeated tests are done on a single sample,The results are usually spot on for each test done.If several tests are done with a salifert alk kit (or similar),same sample,the results of each test will be off (and vary)by a fair amount (test kit noise,and user error i suppose).So for me,I know when my corals look there best and this correlates to 8.5dkh on the hanna.I can keep it much more stable this way by having a good constant to keep my alk tweeked with.Using a salifert kit I would get .5 to 1 dkh variance between tests when actually the alk was very stable.For me a stable way of measuring is the important factor given the instrument is somewhat accurate for our coral keeping purposes.

As far as the Phos checker.This is also a very constant way of measuring low phos levels.Again if it is off by a reasonable amount but I get consistent measurements on the same sample tested three or 4 times,I know this # is somewhat trust-able.On the contrary,if I get 4 significantly different readings from several tests done on the same sample with test kits,I find this # not trust-able.
I agree 100%, I have the same inconsistent results with my salifert, I am satisfy to get consistent result with the hanna test kit, I have just adjusted my target to were my corals look best to me.

[007Bond]

I agree 100%, I have the same inconsistent results with my salifert, I am satisfy to get consistent result with the hanna test kit, I have just adjusted my target to were my corals look best to me.

I agree, if I adjust to where coral looks best using my Hanna as my point of reference I think this is the answer. My Hanna is consistent, quick and easy. The heck with -18% of read out, the look of the coral is the correct answer.

[Sport507]

I check my Hanna against the Salifert and the difference was .1dKH. The Hanna was higher .1 dKH.