Salifert v. Seachem Ca Test Results

[Habib]

Lee, in addition to what I find for Red Sea salt here is a few years old study showing the same value (360 ppm).

http://saltaquarium.about.com/gi/dy...om/fish2/aqfm/1999/mar/features/1/default.asp

Yes, I know salts can change.

 

[leebca]

Trying to separate the marketing from the hype from the facts from the anecdotal from the chemistry. . .

I've contacted a marine aquarium analytical lab (they do marine water analysis for public and private aquariums, hobbyists, etc.) for their opinion. A calcium test kit should yield the same result as the AAS analysis. But the contact did indicate that sometimes the so-called calcium test kit suitable for salt water really doesn't work well with salt water. Otherwise, the numbers from such test kits should match the numbers found by AAS.

We should be able to expect reasonably accurate results from our Ca test kits (at least those that work properly with salt water).

 

[leebca]

Thanks Habib. And of course there's also such 'tests' (also old) of Red Sea by the University of Missouri, and a US. Government prime contract testing laboratory, Environmental Trace Substance and Technology
http://www.aquacraft.net/w0022.html

As the above shows, the Red Sea Ca ranged from 277 to 417 at 1.026. Salts change? More than that. Salt composition can change from batch to batch from the manufacturer.

Only thing is, Habib, I make my salt up to 1.023. I'd expect lower than expected Ca concentrations at the lower sp. gr.

But you fall back on what it should be rather than what it is. I'm not keen to know how my kit performs theoretically, I prefer to know how it performs in actuality. I don't think what the Ca concentration should be and what the test kit says it is, is of any value to me. I want to know what the Ca concentration is and what the kit says it is.

Very simply. I make a batch of salt mix and test for Ca with four test kits. Two give me almost identical results, the third is 10% higher, but one is 25% higher than the two that agreed. Regardless of what the Ca concentration should be, I want to know what the solution I just made up contains.

I cannot make an informed decision on which salt I would like to use unless I know what I'm buying and what I'll have to supplement to get the parameters I want. This I want to directly measure, rather than read a report or manufacturer's analysis.

I will be trying out a new salt soon. I will make up a batch of water for a water exchange from that salt in a couple of weeks. I will sample that and have it analyzed by an analytical laboratory (for several constituents including Ca) and I will use all four test kits (Salifert, LaMotte, SeaChem, and Hagen) and maybe different lots of test kits bought from different parts of the country, including available 'fresh' kits of Salifert and compare those Ca results to the AAS.

Maybe from the above, I can share more data. :rollface:

 

[steve the plumb]

I tested 700 with the salifert but my friends mag level was at 1560 ppm.I don't know if that plays a role.We both use red sea salt.I never test the mixed salt I am adding to the tank.I only test the water from the tank.If I am to add a cal supplement I will wait a day to test.then retest 3 days later.I have the seachem test kit that uses ro water in the small reddish pink vial.Is this a good test kit?It wasn't cheap.I will buy another test kit to see the diff between but I have not gotten around to it yet.

 

[Habib]

I tested 700 with the salifert but my friends mag level was at 1560 ppm.I don't know if that plays a role.We both use red sea salt.I never test the mixed salt I am adding to the tank.I only test the water from the tank.If I am to add a cal supplement I will wait a day to test.then retest 3 days later.I have the seachem test kit that uses ro water in the small reddish pink vial.Is this a good test kit?It wasn't cheap.I will buy another test kit to see the diff between but I have not gotten around to it yet.

The magnesium concentration varying from very low to very high has no significant impact on the calcium measurement using the Salifert.

A few weeks ago I had someone who measured a calcium of more than 600 ppm on his tank and he was using the Red Sea salt. I asked him to measure the waterchange water and he found 340 ppm.


I would check also the water change water. FWIW if it is the Oceanic salt then it is very likely that also the water change water has a very high calcium concentration.

 

[Habib]

But you fall back on what it should be rather than what it is. I'm not keen to know how my kit performs theoretically, I prefer to know how it performs in actuality. I don't think what the Ca concentration should be and what the test kit says it is, is of any value to me. I want to know what the Ca concentration is and what the kit says it is.

I agree, except on the part that I fall back on what it should be rather than what it is.

We too want to know what the calcium concentration is and what the kit says but in addition to that we want the kit to say exactly the same as what the true calcium concentration is.


We use certified standards, we use various natural seawaters for which the calcium concentration is known, we use some own made standards, we spike natural seawater with ceriftified standards and besides that we have several other checks.

They all show that our kits give the correct value.

A few examples I gave above using Hobster's batch of reagents.


In addition to it the Salifert gives values for calcium using various saltmixes as claimed by the manufacturer or lower. Certainly not 25% higher.


Regarding using AAS and such...I don't trust results unless all details are given and is shown to have been performed correctly.

I know that there are many sources of errors using $50,000 or even more expensive equipment.

Randy has shown that he had difficulty in getting accurate values using ICP.
We did it in the past and could get accurate results only with a LOT of effort.

Because I don't trust values obtained with such equipment unless all details are give,therefore , I also did not direct anyone to various studies conducted in such ways which btw show that the Salifert does not give too high results.

Only thing is, Habib, I make my salt up to 1.023. I'd expect lower than expected Ca concentrations at the lower sp. gr.

Your first post mentioned 1.025. However, if the Red Sea has consistent batches and gives 360 ppm at 1.026 then at 1.023 it would be approx 330 pm. Still much higher then the Seachem's 260 value and still very close to what you found with salifert.
FYI, the Red Sea salt report you gave is known as the S-15 report and you will find a lot of critisism on that report.





Having said al this...I see you are a chemist...do you have calciumchloride dihydrate in the lab?

 

[Habib]

Because I don't trust values obtained with such equipment unless all details are give,therefore , I also did not direct anyone to various studies conducted in such ways which btw show that the Salifert does not give too high results.


This is waht I said in my above post. However I found a recent analyses, albeit for the magnesium kit and not the calcium, which might be trustworthy because the person knows what he is talking about and has shown analyses using a large range of standards using HR-ICP-MS.

I will try to contact him.

The magnesiium kit of ours also conatins, just like the calcium kit EDTA but in a higher concentration. We use the same seawater samples for calibration as we use for the calcium kit.

We also know the exact concentration (EDTA and water).

So it is justified to look at the values obtained with the magnesium kit.

They used water with 1540 mg/L magnesium. I assume seawater because the author explained how difficult a seawater matrix is and apperas to know what he is talking about.

They used 4 brands of kits and for the Salifert they took 2 different batches. Our Mg kit's resolution is 24 ppm (size of 1 drop).

Here are the results (if it asks to download something you can press cancel):

http://www.korallenriff.de/Beckum_2005_am-Dateien/frame.htm#slide0072.htm

 

[leebca]

Sorry Habib et al, I was unable to post any sooner.

I agree, except on the part that I fall back on what it should be rather than what it is.

We too want to know what the calcium concentration is and what the kit says but in addition to that we want the kit to say exactly the same as what the true calcium concentration is.

if the Red Sea has consistent batches. . .

I don't imagine anyone can or should assume that a mixture of dry salts, dissolved, has a determinable calcium concentration. There are too many variables to depend upon any dry salt mix assay to know the final calcium concentration. The best assurance is a single calcium salt, which isn't sea water, unfortunately.

. . .we use various natural seawaters for which the calcium concentration is known. .

Known how? Using the Salifert kit? If you're going by general assays and not actual measurements, I can see a source for error.

I don't trust results unless all details are given and is shown to have been performed correctly.

My sentiments exactly, regarding LaMotte, Salifert, SeaChem, etc. calcium test kits.

My education was quantitative analytical chemistry. But I don't work in that field. Our company lab is a metallurgical lab, but calcium chloride dihydrate is available.

I work for a manufacturer. We know everything about our competition that can be gathered from having and testing their product. We know our competitor's strengths and weaknesses, as well as our own. Comparative product performance is just one tool. However, since you don't seem to know these things of your competition, I'm moving forward on the project I indicated.

I have several test kits on their way to me now for comparison. You most likely won't trust the results (from your quote), but for me they will determine what test kit to rely upon.

Live long and prosper!

 

[leebca]

Part of the mystery on why Habib was saying that the Red Sea Salt should give a Ca concentration of 360, which the Salifert Test Kit measured. . .

In gathering Ca test kits for my project of comparing Calcium test results, I obtained a Red Sea Test Kit for Calcium.

In their insert they mention that a solution of Red Seal Salt will measure about 360 ppm Calcium. But, it says in their insert that they are assuming that 100 ppm comes from the source water used to make up the salt solution. They assume that most everyone has up to 100 ppm Ca in their tap water. They warn that if the solution is made up of something other than tap water, then the Calcium would be lower.

I made my Red Sea Salt mix up with RO/DI water which measures less than 5 ppm Ca. Thus, I should expect about a 250 ppm Calcium using their mix (assuming their mix is perfect at each batch, which I don't have a lot of faith in). Their figures are based on a 1.026 sp. gr. Mine is a bit lower sp. gr.

The SeaChem and other test kits I used where closer to the anticipated 250 ppm Ca in the RS Salt Mix, except for the Hagen (about 10% higher) and Salifert (about 25% higher).


---------------

So far I have 10 test kits on hand and I'm waiting for a few more to arrive. I'll post results by Labor Day in another thread.

:rollface:

 

[Habib]

In their insert they mention that a solution of Red Seal Salt will measure about 360 ppm Calcium. But, it says in their insert that they are assuming that 100 ppm comes from the source water used to make up the salt solution. They assume that most everyone has up to 100 ppm Ca in their tap water. They warn that if the solution is made up of something other than tap water, then the Calcium would be lower.



My Red Sea kit says something different.

closer to the anticipated 250 ppm Ca in the RS Salt Mix

That is therefore a wrong conclusion.

Please quote exactly what your Red Sea kit says.

 

[leebca]

My Red Sea Insert says:

SPECIAL NOTE: Tapwater always contains Calcium (up to approximately 100 ppm). When you dissolve Red Sea Salt in tapwater the resulting Calcium level will have an optimum value (450 ppm of Calcium). A light amount of surplus Calcium may even precipitate out, forming Calcium Carbonate.

Users of Reverse Osmosis water, will obtain a slight lower Calcium level under the same circumstances. Since most of the Calcium has been removed by the Reverse Osmosis process. For these aquarists we advise to add Calcium to their R.O. Water for example by putting coral sand, crushed coral or dolomite in their water storage tank, or by using a Calcium additive such as Red Sea's Reef Success Calcium.

Thus, in my case, I'd expect about a 355 ppm Calcium on the Red Sea makeup water, which was what the Salifert Test Kit said it was, but 250 was the SeaChem result. Then I used the SeaChem reference to do more testing. The span was there on that reference sample. It was apparent to me (and still is) that a wider sample selection needed to be tested, with a wider selection of test kits, and the AAS.

Habib, when you earlier wrote:

When I mix Red Sea to a salinity of 35 I find 360 mg/L
Red Sea , IIRC, also claims it to have that value.

what were you using as the source water? Why were you assuming what my Calcium results should be, not knowing my makeup water content?

I'm still hoping to resolve the concerns through a wider matrix of testing, and the AAS.

 

[RustySnail]

I work for a manufacturer. We know everything about our competition that can be gathered from having and testing their product. We know our competitor's strengths and weaknesses, as well as our own. Comparative product performance is just one tool. However, since you don't seem to know these things of your competition, I'm moving forward on the project I indicated.

I have several test kits on their way to me now for comparison. You most likely won't trust the results (from your quote), but for me they will determine what test kit to rely upon.

So let me guess... The "results" you will be posting will likely indicate that the Ca kit of choice will be "Brand X" which just so happens to be made by the company who employs you? And all the while you have been bashing one of the leading suppliers of high-quality testkits who's owner has always been helpful, responsive and patient with customers regarding concerns and problems associated with his product...

:thumbsup: Habib for weathering this storm...

I'm still concerned over the discrepancy between Salifert/Seachem but at this point I am more inclined to believe that the Salifert kit is correct and the Seachem/Reference is off by a fair bit.

 

[BeanAnimal]

Im kinda lost here....

Where does leebca work and where was this disclosed? I see mention of him working for a metilurgical lab, not a manufacturer of test kits or reagents.

 

[leebca]

BeanAnimal gets points for intelligence.

No points for RustySnail.

I work for a company that manufactures high pressure aluminum gas cylinders. I am a marine aquarium hobbyist of 36+ years. One degree in Chemistry; one degree in Microbiology, from OSU.

It's interesting to note that my posts are being taken as 'bashing' at least by one willing to write about it. I think I was and am still keeping an open-mind here. I want to know the facts and right now, there is too little information to come to any informed decision. As I stated much earlier, both Salifert and SeaChem are reputable organizations. Errors and weak assumptions do occur. But as the top post of this thread states, I can't make a credible Calcium addition when test results show a large range of possible Calcium concentrations.

Regarding Habib's involvement and contributions: Many people have done that in our hobby. Yet what they have to say and believe doesn't mean it is fact or truthful. I am appreciative of his involvement --- of EVERYONE'S involvement here at RC.

It's amazing to me, having read thousands of posts here and on other forums, how one minute the posts run from "don't trust him/her/them, because all they want to do is sell" to "he's a good guy, believe him." The fact is, I separate the information from the source and give no more credibility to the owner of a company or name on a product (e.g., Julian Sprung, Mark Weiss, etc.) than to the novice who just reported an event. Our hobby is full of anecdotal information. I mostly trust the published scientific studies, but even they are tainted by the occasional competition for grant monies.

It's rare we can investigate for ourselves in this (overly expensive) hobby. (I'm unsure what I will do with all these left over kits!) I will do investigative work when I can and I will share the information. As an undergraduate at OSU I studied Cryptocaryon irritans, use of antibiotics to fight it (including garlic), dips and baths, immunity, and fish nutrition. I was funded for these projects. It's much harder on your own!

It may surprise the readers of this post that all I will be providing is data and results, no conclusions. This is not a scientific project or study. Draw your own conclusions. But, RustySnail, just do your own study and stop reading my posts if you are convinced my motives are of such low integrity.

 

[RustySnail]

Where does leebca work and where was this disclosed? I see mention of him working for a metilurgical lab, not a manufacturer of test kits or reagents.

It was not disclosed; it was simply an inference based on how that post was written. It's a common marketing ploy to discredit the reputation of an otherwise good/superior product by use of innuendo, skewed analysis, etc. Just look at that 'Aquacraft S-15 Report' for starters. The reason I question leebca's intentions is stated in the following (quoted from leebca):

The fact is, I separate the information from the source and give no more credibility to the owner of a company or name on a product (e.g., Julian Sprung, Mark Weiss, etc.) than to the novice who just reported an event.

I for one dont give more credibility to leebca than to Habib; but IME people like Randy, Habib, et.al. are usually right (especially when they are talking chemistry and in Habib's case his own product)

I do give more credibility to people recognized as experts than those considered novices; I think you will find a consensus of opinion on this subject in science, industry, and law.

It may surprise the readers of this post that all I will be providing is data and results, no conclusions. This is not a scientific project or study. Draw your own conclusions. But, RustySnail, just do your own study and stop reading my posts if you are convinced my motives are of such low integrity.

Posted data/results will be enough to 'draw conclusions'. If those results are flawed; the conclusions drawn will be incrorrect. Whatever your 'results' are; I will not be giving them a whole lot of credibility based on your prior posts/opinions (and statements like the one I quoted). I'm still waiting to hear Seachem's take on this issue (I posted a link to this thread last week); and if there were going to be some qualitative comparisons made I would prefer them to be done by a known expert who known to be is non-biased (like the report Randy did on pH calibration solutions).

 

[badpacket]

OK, lets all stop and count to 10, slowly.....

Rusty, your inference was off. I'm sure a few people were wondering something similar, however leebca has apparently better than the average poster's credientials from an educational perspective on Chemistry, and doesn't seem to be part of a ploy by a competitor. I'm sure leebca will post not only the results of his testing but also his testing methodology to insure it meets acceptable levels of rigor that most here can appreciate.

Habib has indeed been one of the best Manf's reps on the board, and has a track record of helping out anyone who has a question, whether it concerns his products or not. So, I think we should see what leebca discovers as a result of his testing, and not pre-judge anyone, nor assign motivations for their posts.
I understand and have faith in Habib, and also find leebca's comments intriguing and scientifically valid. Both of these fellows could be potential Chemistry Einsteins for all I know, but I do know that Einstein made mistakes like the rest of us, so it does happen. There appears to be an anomoly who's solution is not readily apparent, if there's a forum in the world where this would be germane to hash it out, its this one.

From my limited knowledge of Chemistry and the various reference agents used by some kits, I would think it better to test against a known saltwater sample as that is ultimately what we are looking to test.

 

[Habib]

OK, lets all stop and count to 10, slowly.....

Yes, please!

I have no time now to read the posts (have only skimmed through them) and respond but will later today.

 

[JakStat]

I do think it's possible that one manufacturer's standard might be optimized for that brand.

For example, it's been suggested that the standard might be just freshwater solution of calcium, but this would have a poor shelf life. If it's in some sort of buffer/preservative like Tris-EDTA or Tris-borate, saline-EDTA, etc then titrant or indicator could be formulated accordingly, and subsequently dedicated to Seachem kits only.

It would be nice to hear from Seachem regarding their standard.

 

[boxfishpooalot]

well, for one I prefer Saliferts test kits for one very important reason. Customer support here on Rc.

#1 is seachem going to help you like Habib can? I dont think so.

I was once having problems checking my ammonia results for salifert ammonia test kit. I found a light brownish haze in my sample after the test. So not knowing what the color should look like I posted my problem to habib. He ended up taking pictures of each ammonia result from 0-2ppm! Ended up being super easy to understand where I was at for ammonia. THANKS Habib!

Now thats customer service. Seachem gunna do that for you? I dont think so.

 

[Shoestring Reefer]

well, for one I prefer Saliferts test kits for one very important reason. Customer support here on Rc.

#1 is seachem going to help you like Habib can? I dont think so.

...

Now thats customer service. Seachem gunna do that for you? I dont think so.

SeaChem helped me out like that!

I had some powdered reagent go bad, I stored it improperly and it got moist. It still worked as far as I could tell, but I didn't get that warm, fuzzy fealing using it. SeaChem sent me a replacement, no cost for the reagent or the shipping, and I got it fast. And I did it all through RC! AND I'm not the only one, I got the replacement after reading about someone else getting great support from SeaChem.

It looks to me like you wrongly bashed SeaChem, why don't you get your facts straight. Maybe post something like, "I like Salifert because of their great customer support. Here's my experience, any one had a similar one with SeaChem?"