HANNA just came out with the new calcium test kit. Has anyone use it and what is your opinion?
I just got mine and now I’m skeptic about the test. I’ve been testing with API calcium test kit for ever (I know it’s not the best test kit in the world) and been keeping the calcium in the 420 to 460 range since this tank been set up according to API. Now, I’ve tested my calcium level with the new HANNA kit and it shows 365 ppm for my initial test. I was astonished by the number so I retest it again. The number was not the exact 365, but 372.
OK, so the variation of the test is some what close to each other so, I take it as being mids 300. Either way this result is very low to me and I don’t know how my corals have been surviving in my tank with such a low calcium levels. So, for the next couple of weeks I will up my calcium and will test alk, mag as well to see if that need to be up to get my water up to the proper levels.
I wouldnt up anything untill you verify the meter read. Is it a hand held photospectrometer? I see two vials so i assume one is to zero off of, and the other is the sample test cell? What is the reagent? and does it have you use DI water for the zero or the tank water?
Let me know what the reagent is and ill look it up at work and get a better idea of what its doing…
Yes, it is a hand held photospectrometer. No, it comes with 2 vials, but you use the same vial for zero then the measurement after you add the sample water and regent B.
The zero regent A is sodium tetraborate decahydrate solution. It does not state what regent B is.
Yes, to zero you must use DI water and regent A.
This statement is from their web site.
The HI 758 Calcium Checker®HC is extremely simple to use. First, zero the instrument by adding Reagent A and deionized water into the vial. Insert into the HI 758 and press the button. Next, remove the vial and add 0.1ml of sample and add Reagent B; shake to dissolve. Reinsert into the Checker®HC and press the button to read the calcium concentration in ppm on the display.
it i nice but the di water has to be 100% pure for accurate results there are a lot of complaints about it that is why i held off, but all results were higher due to calcium in the water i think you are accurate with your testing i hava a seachem reef status i could confirm for you, used to use salifert but they were out when i needed one. check rc under the hanna forum you can read all the comments there about it also a lot are asking for liquid reagents
How many ml di are you adding to the vial? If you think about the dilution factor, like .1 ml to the di then the multiplier to get your reading the results imo could be way way off. Most of the time photospectrometers are used only for the low range testing of ca, hence the dilution they are using to perform the test. Get dunk to verify it for you before you dose, I’m going to order some reagent from hach in the near future, then ill test it for you in the lab here at work.
[quote=“dunk, post:5, topic:4801”]
it i nice but the di water has to be 100% pure for accurate results there are a lot of complaints about it that is why i held off, but all results were higher due to calcium in the water i think you are accurate with your testing i hava a seachem reef status i could confirm for you, used to use salifert but they were out when i needed one. check rc under the hanna forum you can read all the comments there about it also a lot are asking for liquid reagents[/quote]
Thanks Tim. I use my DI water from my RODI unit with 0 TDS. I don’t know how much purer it needs to be. I guess I should have read about it before I drop the money on it. And I guess I need to get with you and do some water testing.
[quote=“aonemarine, post:6, topic:4801”]
How many ml di are you adding to the vial? If you think about the dilution factor, like .1 ml to the di then the multiplier to get your reading the results imo could be way way off. Most of the time photospectrometers are used only for the low range testing of ca, hence the dilution they are using to perform the test. Get dunk to verify it for you before you dose, I’m going to order some reagent from hach in the near future, then ill test it for you in the lab here at work.[/quote]
I just add 0.1 ml per the instructions. As for the dilution factor, that is way too far for my scientific knowledge. I have no idea, I just follow the instructions. I will get with Tim though and see what I can come with.
If the rodi system is producing 0 tds then there should be 0 ca. A quick check would be using the api test kit on the rodi water.
It should turn blue right off the bat. I just tried it here at work but was using a total hardness test and it went blue just from the primary reagent.
I have the Hanna Checkers, for Alk, Phosphate and Calcium
calcium is the hardest one, I changed to a 3ml syringe to measure the 1 mil, as I hated their markings on their syringe. But after that mine has tested very close within 20 to 30 ppm to my Salifert and Red Sea Pro test kits and the results a repeatable to within a few ppm.
I’m dreaming of the day we just have probes for everything and just calibrate once a month and check the controller for daily readings
[quote=“Hudzon, post:10, topic:4801”]
I have the Hanna Checkers, for Alk, Phosphate and Calcium
calcium is the hardest one, I changed to a 3ml syringe to measure the 1 mil, as I hated their markings on their syringe. But after that mine has tested very close within 20 to 30 ppm to my Salifert and Red Sea Pro test kits and the results a repeatable to within a few ppm.
I’m dreaming of the day we just have probes for everything and just calibrate once a month and check the controller for daily readings :-)[/quote]
Frank, what do you mean by “I changed to a 3ml syringe to measure the 1 mil”? you mean for it see the line better? but you still only 0.1ml right?
[quote=“aonemarine, post:9, topic:4801”]
If the rodi system is producing 0 tds then there should be 0 ca. A quick check would be using the api test kit on the rodi water.
It should turn blue right off the bat. I just tried it here at work but was using a total hardness test and it went blue just from the primary reagent.[/quote]
With API, does it read low range or does it matter if it turn blue right away, meaning no CA at all or because it a trace it would not show up? and would a trace of CA affect the end test result even with 0 TDS? when you put the RODI water with reagent A to 0 it. wouldn’t the tester go defult and not do the read since there is CA in the vial or does the reagent cancel the trace that’s in the vial? hope these questions are not confusing.
Thanks Ken I never knew consumer level CA probes were avaialble, I might just buy one of the PinPoint CA Probes, while I’m waiting on APEX to come out with one for the controller.
[quote=“reefman66, post:12, topic:4801”]
Frank, what do you mean by “I changed to a 3ml syringe to measure the 1 mil”? you mean for it see the line better? but you still only 0.1ml right?[/quote]
I Use the 3ml syringe to mesure the 1ml of regent A it was hard for me to tell the fill mark on their 1ml syringe
for the .1ml of tank water I fill to .5ml and depress to .4ml
[quote=“dunk, post:8, topic:4801”]
well a one will know this better than me but i think that some water even through ro/di can have calcium in it[/quote]
[quote=“aonemarine, post:9, topic:4801”]
If the rodi system is producing 0 tds then there should be 0 ca. A quick check would be using the api test kit on the rodi water.
It should turn blue right off the bat. I just tried it here at work but was using a total hardness test and it went blue just from the primary reagent.[/quote]
Here is their statement on DI water.
It’s important to use good quality RO/DI water. Any residual calcium in the RO/DI water will be magnified during the testing procedure and can result in a false positive/out of range reading. Even levels of calcium undetectable by a TDS meter (which could be 3-4 ppm, even if the meter reads 0) will skew the reading. Use HI 70436 (3.75 L) or HI 70436M (250 mL) Hanna triple filtered RO/DI for best results.
yes, there are a lot of digital monitors out there. but gets pretty expensive and time consuming to keep calibrated , and then set up remedial solutions activated by a controller. might just as well use an API test now and then and add some GFO, LaCl, Carbon and a big fuge. I guess i just eyeball the tank to figure out whats going on. dosing the suplements by controller driven by a probe monitor is ok, but not sure how having continuous digital monitors of nitrates, phosphates can help. what would you dose.?
I’m trying to type this out on my phone and its a pain to explain like this so I hope it makes sense.
When testing water you are looking at the concentration of something in the water.
The hanna meter is really only testing the .1 ml of tank water, the rodi water is the dilution.
For the test to be correct, think of how small the sample is, then figure how far off your test could be if your sample was .11 or if it was diluted .1 too much. Would throw your readings way off. Accuracy is key on small samples.
Now back to the measuring of concentrations, if you have 450 ppm/ca in a 500 m/l sample of tank water and you dilute that sample with 500 m/l rodi, then retest the sample you will have a 225 ppm/ca read. Being your sample has been diluted 50% you need to multiply your read by the dillution. 225 * 2 is 550 mg/l.
The same can be done in reverse on some tests, by evaporation the sample down to increase the concentration. Not the best thing to do accuracy wise but if your searching for 1 ppm of ca in your rodi, its probably ok just to get an idea of what’s going on.
Zero tds is 0, now can your tds meter really read a true 0? How do you know? You buy a standard and read it to verify the meter.
Now that api test is not the most accurate, but for a down n dirty on the rodi it should be ok. Just add the drops from bottle 1 then 1 drop or less from bottle 2, it should be all blue no pink on the first drop, evaporation down the sample before you test wouldn’t be a bad idea, or bring me some of your rodi and ill run it here and check it down to 1 ug/l.
Ok eyes drying out now… Gtg.
A, if you can make it to the next meeting will you bring a sample of your water? i’d like to test it. last month paul, tim and i tested Mg of Pauls water. we each had a diff brand kit, and all got close results. I’m curious if my api kit reads closer to your kit, or your new toy. Those Hanna’s are pretty sweet ::
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