Marinemix Bioassay analysis results

[liquid]

If that is the case (that cobolt could be one of the causal agents), then why did the urchin larvae have better survival rates in that particular mix? Apparently they have a high resistance to cobolt? FWIW, according to the second page of the final link you posted, Artemia salina have a toxic dose around 10-17 mg/L and many similar organisms have toxic doses in a similar range.

Shane

 

[Habib (Salifert)]

If that is the case (that cobolt could be one of the causal agents), then why did the urchin larvae have better survival rates in that particular mix? Apparently they have a high resistance to cobolt? FWIW, according to the second page of the final link you posted, Artemia salina have a toxic dose around 10-17 mg/L and many similar organisms have toxic doses in a similar range.

Shane

It was a very quick search but nevertheless some algae seem to be sensitive to it.

Ron did study development of the very early stage after the egg fertilization and that seems at a first glance not that sensitive :

http://www.pesticideinfo.org/List_Aquir ... c_Id=AQ354


Here are some tox data for molluscs and some phytoplankton:

http://preview.pesticideinfo.org/List_A ... offset=200

 

[Habib (Salifert)]

Here is an interesting abstract which shows the inhibition of growth at a sub-ppm concentration of cobalt in some phytoplankton. The amino acids they mention are not unlikely in an aquarium:

Authors: Alicja Kosakowska



Title: The Effect of Amino and Polycarboxylic Acids on the Toxicity of Cobalt to Phytoplankton Cells



Source: Oceanological Studies

year: 1996, vol.: 25, number: 4, pages: 47-54

Keywords: amino and polycarboxylic acids, cobalt, chlorophyll a, photosynthesis, cyanobacteria, green algae

Language: English

Document type: article


Publication order reference:

Alicja Kosakowska

Institute of Oceanology, Polish Academy of Sciences,

ul. Powstancow Warszawy 55, 81-712 Sopot, Poland



Abstract: The effect of the amino acids l-cysteine (CYS-SH), l-aspartic acid (ASP-OH) and l-glutamic acid (GLU-OH), and of polycarboxylic acids (PCAs) on the biological activity of cobalt in cultures of Scenedesmus armatus (Chodat) and Synechocystis aquatilis (Sauvageau) was investigated. The influence of metal ions was determined by measurements of chlorophyll a content in the cultures and rates of carbon fixation by the phytoplankton cells.

The addition of cobalt (2.5 10-6 M) to the cultures caused inhibition of growth, monitored by the chlorophyll a concentration and the photosynthetic rate of both green algae and cyanobacteria. It was found that these acids significantly increased the chlorophyll a content in both algal species when treated with cobalt.

Polycarboxylates, CYS-SH and ASP-OH also increased the rate of C-14 incorporation into algal cells in both cultures, whereas GLU-OH was effective in cultures of Synechocystis only.

The results indicate that organic compounds, polycarboxylates and amino acids modify the biological activity of the cobalt. The environmental consequences of these processes are considered.

 

[liquid]

For reference purposes:

Richard Harker's results (mg/L):

Aluminum .23
Boron 7.8
Barium .034
Cobalt 24.
Chromium .046
Copper .009
Lithium 8.4
Manganese .0036
Molybdenum .007
Lead .05
Strontium 4.4
Zinc .003

Manufacturer's reported results (taken from Ron's article), ppm:

Aluminum 0.17
Boron n/a
Barium 0.050
Cobalt 0.000
Chromium 0.001
Copper 0.001
Lithium 0.110
Manganese 0.001
Molybdenum 0.010
Lead 0.004
Strontium 12.50
Zinc 0.014

Shane

 

[rharker]

Was it exactly the same method that Ron used (ICP), or was it ICP-MS?

Hi Randy. It replicated Ron's work. It was ICP.

 

[Habib (Salifert)]

This is somewhat off-topic but I could almost swear that the table you took from was not there when the article was published.


I really wonder why Ron did not look at aluminum because he noted that it was very high and did not comment about it. :roll:

 

[rharker]

If Si does not show up the Al2O3 becomes (IMO) much more likely.

Silicon measured 0.41 mg/l compared to Ron's IO of 1.50

 

[liquid]

I really wonder why Ron did not look at aluminum because he noted that it was very high and did not comment about it.

I wondered that, too, about a couple things. :shrug:

I think we're going to learn a number of interesting things from both Richard's and Inland Reef's testing. Between what's been currently raised and the auctions that are going on right now, we will definitely have some interesting things go discuss in the months to come after the testing is complete.

FWIW, if aluminum is a problem the manufacturer should be able to reformulate using a fumed SiO2 anti-caking agent.

Shane

 

[randy holmes-farley]

A kind of zeolite containing besides Al also Si might be more likely.

I agree. And I know that you understand my comment Habib, but others may not, so I'll explain. I only mentioned the aluminum oxide because some aquarium manufacturers thought that inert as well. I see no reason to believe that other aluminum-containing compounds are "inert", but I've not tested any except aluminum oxide.


If the Al measurements by Ron were correct then the IO contained about 0.11 ppm and tanks which he tested contained on average 0.17 ppm Al.


My comments on the correctness of Ron's aluminum tests are here:

http://www.advancedaquarist.com/issues/ ... 3/chem.htm

This sentence sums up a lengthy discussion:

"I am skeptical that all of the values in the survey above represent real measurements of aluminum rather than noise in the ICP since they are all right around the limit of quantitation for aluminum in seawater. "

 

[randy holmes-farley]

FWIW, in the above article of mine, I could not truly detect aluminum by ICP in either IO or my aquarium, despite the fact that you can integrate the noise and get a number.

FWIW, I think these kinds of tests and interpretations are significantly more complicated than some allow.

 

[randy holmes-farley]

Hi Randy. It replicated Ron's work. It was ICP.

Thanks, Richard.

 

[rharker]

"I am skeptical that all of the values in the survey above represent real measurements of aluminum rather than noise in the ICP since they are all right around the limit of quantitation for aluminum in seawater. "

Randy, nice article. The following may strengthen your skepticism. My tank measured .24 and a friend's tank measured .23, and the kicker is that a pristine reef in the Pacific measured .20. There seems to be a pattern.

Richard

 

[jamesw]

Very interesting Richard. I look forward to seeing more results.

Cheers
James

 

[DonJasper]

Well I debated between starting a new thread and bringing up and old one, to ask my silly questions.

I think we're going to learn a number of interesting things from both Richard's and Inland Reef's testing. Between what's been currently raised and the auctions that are going on right now, we will definitely have some interesting things go discuss in the months to come after the testing is complete.

Ok. So we'll have columns of numbers of exquisite accuracy. The chemists will insure that. So how will we know which salt is the best one to grow corals?

FWIW, if aluminum is a problem the manufacturer should be able to reformulate using a fumed SiO2 anti-caking agent.

Won't a "New and Improved" sticker on the salt bucket , or even the rumor that the formulation changed, invalidate the study results for a given manufacturer?

 

[MattM]

Ok. So we'll have columns of numbers of exquisite accuracy. The chemists will insure that.

Yup, that exactly what we hope to get!

As has been said somewhere before, I don't think this will be the ultimate answer to all questions concerning salt, but it is an essential first step.

Discussions like this and the insights of Habib, Randy, Richard and many others will help to anwser a lot of the questions. Getting those columns of numbers is the foundation we need to start the discussion.

Won't a "New and Improved" sticker on the salt bucket , or even the rumor that the formulation changed, invalidate the study results for a given manufacturer?

Perhaps. If the study goes as well as we hope then it will get enough publicity that the salt manufacturers should take notice. If one changes their formula as a result, we'll ask them for a donation to get their salt re-tested. If this approach works, we'll have a constantly updated online database of salt analyses.

That can't be bad...

 

[DonJasper]

As has been said somewhere before, I don't think this will be the ultimate answer to all questions concerning salt, but it is an essential first step.

**WARNING** Good nature required past this point. Those with a tendency to flame should live a full and meaningful life without reading past this point. **WARNING**

Scientist arguing with engineers over what is 'good enough', while the marine biologists are out in boats. Is this a great country or what? (Sorry Habib - it's my Patriotic Duty to perpetuate the arrogant USA stereotype). LOL!

No doubt those that Know More Than Me (chemically speaking - I do have _some_ professional pride :wink: ) will have a blast unraveling the industrial processes used to produce the salts. I know I would.

Someday I'll have to figure out what the second step is - and how it builds/requires the first step