Hannah Alk Checker reading

[Der ABT]

Just wanted to see what others are getting for readings.

ive heard alot of they read higher then what the actual alk is, and ive hear others say they are right on point.

 

so was hoping to hear what people's read, and then what alk the believe that to be.

 

thanks in advance

[Ryan S]

Just wanted to see what others are getting for readings.

ive heard alot of they read higher then what the actual alk is, and ive hear others say they are right on point.

 

so was hoping to hear what people's read, and then what alk the believe that to be.

 

thanks in advance

 

i did mine yesterday. API was 8.0 dkH. Hanna was 7.5 dkH.

[Der ABT]

Sorry i guess what i meant to ask is what is the reading the hannah checker gives, gussing for 7.5 was 130 or so.

 

just curious what people are using as a target number for the alk they want....aka i want 8 alk, so i shoot for 140 on the alk checker.

[Ryan S]

Sorry i guess what i meant to ask is what is the reading the hannah checker gives, gussing for 7.5 was 130 or so.

 

just curious what people are using as a target number for the alk they want....aka i want 8 alk, so i shoot for 140 on the alk checker.

 

My reading was 134.

 

140 would be 7.84 dkH.

 

143 would be 8.00 dkH.

 

Randy Holmes says here that 7-11 dkH is the ideal range (thus making 9 dkH more ideal than 8 dkH).

 

161 would be 9.01 dkH. I am considering trying 161 myself. Still researching it however.

[gizmoody]

I try very hard to keep at 160. That's about 50 mls/day alk dosing. The Red Sea Coral Pro Salt I use has a kH of 12.2 which is apparently good for fast coral growth. My kH is never that high though.

[Origami]

I typically read out around 145 on my Checker. When I first purchased it, I made up a DIY alk reference solution and ran it in the checker. The Checker was right on target.

[Big Country]

The newer Salifert alkalinity test kits come with a bottle of reference solution that I've checked my test kit with. I would assume it could be used to check a Hanna Checker also if you can find someone nearby that has some. I've got two bottles and could give you some if you're up my way.

[Der ABT]

i forgot about the salifert ref solution....would that still work with the hannah though, would i add the hannah checker solution to it or just put the salifert ref solution in once its been zero'd wtih tank water..

 

 

im glad tom is getting his readings right on point, im actually getting very similar readings too from salifert to hannah and wanted to see if it was just me or what.

thanks all

[scott711]

I usually get 160. If I remember correctly is about 8.8

[BowieReefer84]

Mix some water at 1.026 Then measure Alk in it. Try to maintain that... Consistency is key...

[Der ABT]

Mix some water at 1.026 Then measure Alk in it. Try to maintain that... Consistency is key...

 

 

not sure i would ever just go with the alk thats in fresh water....every salt mix comes out with different numbers and sometimes different batches have different readings (in my experience at least)

 

i was just inquiring mainly to see if people are getting consistent readings compared to other test kits...or if its consistently high or low....was alot of reports of the early checkers reading .5 dkh high compared to other kits.

 

 

again thanks to all for the input.

[BowieReefer84]

Yea, I used instant ocean and added Alk to bring it up to where I wanted it. Some salts like Reef Crystals have higher Alk levels. It would be counterproductive to try and maintain an alk lower than what the salt mixes at. IE: maintaining 8 with reef crystals... Every waterchange would give a swing. Sorry for going off topic.

 

In regards to my Hanna checker it was always VERY close to my salifert kit. I couldn't get a difference worth mentioning as a discrepency at least.

[overklok]

Here is a review of the Alk checker, I have one. It works very well. According the article in advanced aquarist, it reads high by about 50 ppm consistently compared to the Hach titration/pH end-point method.

 

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

[Marc Weaver]

Readings today:

 

Hanna Checker 198ppm (11.1 dKH)

Salifert 11.2dKH

Lamotte 200ppm (11.2dKH)

 

I just checked the alk checker with the Salifert 6.7dKH reference solution and it measured a 118 (6.6 dKH.) With these results matching reputable kits so closely it's good enough for me. I originally thought my alk checker was checking 15% high because I didn't see any SPS growth until my alk reached 10, but now I don't think it was and it must have been something else.

 

 

 

[Marc Weaver]

Here is a review of the Alk checker, I have one. It works very well. According the article in advanced aquarist, it reads high by about 50 ppm consistently compared to the Hach titration/pH end-point method.

 

http://www.advanceda...m/2011/8/review

 

I originally thought mine was reading high as well. 2 months ago I was having STN on the bases of some SPS and no growth at all and even my GSP weren't opening. Alk was measuring 150 (8.4dkh) on the checker and I thought this was fine and couldn't be the cause. After exhausting every other variable I started raising alk by .5dKH a day. I noticed an overnight improvement in polyp extension when I reached 180 (10dkh) and my GSP was wide open and green as could be. I raised it to 190 and held it there for a month. I am finally getting great SPS growth and all of the STN'ed areas are grown back over already.

 

I read the article you mentioned and some interesting reading on reefcentral regarding the checker around a month ago and this 50ppm difference made sense. I bought a new API kit and took several readings and came up with a conversion factor based on what the API was reading and took it from there. I multiplied my hanna reading by .84, then by .056 to determine dkh.

 

When I was having problems, the alk checker was reading 150 on average. With my conversion factor in place, it was 7.05dkh. I noticed the turnaround at 180 on the checker, which after conversion was 8.47dkh, a much safer number to be at. My current readings average 200, which after conversion is 9.4dkh, which is where I want to be. I purchased a Lamotte kit earlier on to verify everything and it always matched the hanna reading very closely.

 

Now for the crazy part: I just ordered a Salifert kit, mainly to get the reference solution and have yet another backup kit. The salifert kit matches the hanna very closely as well and the reference solution measurement with the hanna was spot on as well.

 

Now for the big questions: Are the hanna checker, the salifert kit, and the lamotte kit all wrong? I don't think they are. Something else had to be wrong at the time, but why from just raising alk did I notice a drastic turnaround in 1 week? Why do API and Red Sea Coral Pro tests always test 2 dkh lower than these three? Why don't taxes ever go down? HAHA.

 

Just for reference I will list my other levels that were relatively consistent the whole 2 months this took place.

Calcium 420, Mag 1400, Phosphates 0-.03, Nitrates 2-4.

 

Sorry for the novel and if you made it this far I commend you.

[Origami]

The key to the consistent discrepancy may well be in the subjective nature of the titration end point used in Dana Riddle's approach, quality control in Hanna's reagent (which changed formulation from a powder to a liquid some short time after the checker's release), or possibly in the sampling of Checker's used. For example, it's unclear to me if a single Checker was tested, or if a larger sampling was considered. I suspect that it may be explained by the titration end point. Take a look at this article, for example, http://www.advancedaquarist.com/2002/2/chemistry and look at the tank water titration curve in Figure 1. Note how the pH (left axis) of the sample drops in stages as more acid (bottom axis) is added. Note also, how at pH 4.2 (the recommended titration end point in the article) is just shy of the last plateau (around pH 3.4). If Hanna, Salifert, and LaMotte all transitioned at a lower pH, say 4.0 or even 3.8, then you would expect that their measurements might be higher as more acid titrant would be required to reach the lower endpoint.

 

I'm not sure just why Riddle did not try to validate his results against an alkalinity standard. Even a freshwater standard, which is easily made and measured, could provide some insight into accuracy.

[Ryan S]

The key to the consistent discrepancy may well be in the subjective nature of the titration end point used in Dana Riddle's approach, quality control in Hanna's reagent (which changed formulation from a powder to a liquid some short time after the checker's release), or possibly in the sampling of Checker's used. For example, it's unclear to me if a single Checker was tested, or if a larger sampling was considered. I suspect that it may be explained by the titration end point. Take a look at this article, for example, http://www.advancedaquarist.com/2002/2/chemistry and look at the tank water titration curve in Figure 1. Note how the pH (left axis) of the sample drops in stages as more acid (bottom axis) is added. Note also, how at pH 4.2 (the recommended titration end point in the article) is just shy of the last plateau (around pH 3.4). If Hanna, Salifert, and LaMotte all transitioned at a lower pH, say 4.0 or even 3.8, then you would expect that their measurements might be higher as more acid titrant would be required to reach the lower endpoint.

 

I'm not sure just why Riddle did not try to validate his results against an alkalinity standard. Even a freshwater standard, which is easily made and measured, could provide some insight into accuracy.

 

It's really quite amazing how often I read a post by Tom or Chad and I don't really understand any of it.

[Origami]

It's really quite amazing how often I read a post by Tom or Chad and I don't really understand any of it.

Ha! Sorry. An alternative way to explain the last post is this: Dana Riddle measured alkalinity by adding acid to a sample and watching the pH of the sample drop. He stopped adding acid when the pH reached a certain value. He then used the amount of acid added to calculate the alkalinity of the original sample. Depending upon the stopping point (aka the endpoint) he uses, he can add less or more acid. For example, he would have to add more acid to reach a lower stopping point. If he did this, his alkalinity "measurement" would be higher.

 

Riddle's calculation was consistently lower than the Hanna Checker's estimate of alkalinity. My point is that, given the paragraph above, the consistently low measurement may be partly due to the stopping point being set a bit too high relative to what the other manufacturers are doing.

[Der ABT]

I hated chemistry in highschool and college...i married a Soil Chemist....between her and Tom i actually like reading the explanations, try to put it in my own words and then get told yes or....did you take your meds today??...noo ill go take em now..

 

suprisingly i got what tom is saying and thank yuo much for chiming in...

 

took a reading on a new box of instant ocean and after getting it to temp/salinity let it sit for 4 hours....alk was 11.8?????i always thought IO was low in alk.....my how things vary from batch to batch..

 

thanks again for all the responses.

[Origami]

IO used to mix up to about 11 dKH at 1.0264 sg salinity as I recall. (Confirmed from this post: http://www.reefcentral.com/forums/showthread.php?t=1714505)

0.8 dKH is about 14 ppm CaCO3 units, the units that Hanna uses on their Checker.

[Max Ivers]

I read that article about how the Hanna checker reads about 18% higher in dKH than actual...and since then have been adjusting my results for this.

 

I run a super ULNS with both zeovit and biopellets and so I try to keep a low alk (6.5-7.5) and so I really don't have much room for error in terms of going lower in alkalinity.

 

I have been keeping a calendar with my test results and observations since I started my new tank in August '11 and so I went back and re-crunched the numbers. I found that the times when I thought my alk was perfect at 123 (6.8), my corals stopped growing, began to recede, and my coralline did the same as well, my alkalinity after re-calculating was only 5.6dKH

 

The number I've been at lately is 175 (8.06dKH after adjustment) and everything looks much happier to say the least

 

Tom, how exactly do you make your reference solution??? found the link after some digging, but Tom you really ought to sticky it in the DIY or General Discussion forum so it's easier to find haha!

Edited March 7, 2012 by Max Ivers

[overklok]

How about everyone who has the Hanna and another kit like Salifert, post their test results.

I have been maintaining my alk around 190 PPM on the Hanna kit.

 

My results:

Hanna 195

Salifert 11.2

 

Very close!!!

[Origami]

I found that the times when I thought my alk was perfect at 123 (6.8), my corals stopped growing, began to recede, and my coralline did the same as well, my alkalinity after re-calculating was only 5.6dKH

 

Tom, how exactly do you make your reference solution??? found the link after some digging, but Tom you really ought to sticky it in the DIY or General Discussion forum so it's easier to find haha!

I think an alk of 6.8 dKH (which is 2.4 meq/liter) is too low, personally. It is just a hair under the minimum that I've seen as acceptable, but I personally won't run a tank below 8 dKH because alkalinity drops so easily and quickly. It's easy to lose 1, even 2, dKH in a day's time.

 

As for the sticky, we sometimes sticky too many posts in my opinion. However, feel free to post the link in this thread if you think others would find it helpful.

[Rafal]

I just check mine and my hanna show to me (both at 1.025 sg salinity):

Cube - 129

5g for change - 188 (75% IO, 25% Reef Crystals salt)

Edited March 7, 2012 by Rafal

[GraffitiSpotCorals]

I have always got readings that are very close. I gotta order some more alk bottles for my hanna and some saliferts kits, so when I do that I will post.