Reef Aquaria with Low Soluble Metals Questions

[marke]

Randy,
I have read this article various times, thank you! I don't know how to post it here, but others should read it. Randy discusses ways to add less and export more toxic metals from our tanks.
I have a few questions:
1- Randy you mention "the hypothesis concerning toxic metals is quite reasonable", however no opinion is really offered? You mention---- will use the "premise" that aquarists want to maintain low metals. So Randy how important is this? Does this lead to old tank syndrome as Ron Slimak mentions?
2 You spend a few paragraphs discussing how 2 part is an input of metals however: you go no furthur than to assume that they are made up to be identical to NSW in all elements? An unrealistic assumption in my opinion, especially when using industrial grade raw materials. We have seen in many articles that salt manufacturers can't replicate NSW. Most salt mixes have toxic metals when first mixed. So the question is how toxic is 2 part? Or more specifically calcium chloride, and sodium carbonate? Whats the quality difference between USP and industrial grade raw material as it may affect toxic metal content. Assuming I add a gallon a month of each?

 

[Randy Holmes-Farley Verified Community Expert]

Thanks!

FWIW, this is the article:

http://reefkeeping.com/issues/2003-04/rhf/feature/


IMO, the answer to 1 is still unknown except in extreme cases. Triton allows many reefers to see elevated metals, but in many cases that tank is not apparently suffering. So I'm not sure the state of knowledge as to what levels of what metals has yet changed enough to allow reefers to easily decide what's important and what is not. But I think it will change with more and more data on metals and how the tank looks.

On 2, you are certainly correct that they may have impurities. I say that explicitly in the las paragraph:

"That said, I've seen no independent analyses of any of these products. They may, in fact, not meet their claim of having all ions in natural ratios."

In fact, I'm sure it is true to some extent. But my main point was to get folks to understand the salinity effect with a two part, and how that will lower things again once corrected for, so having say, copper" in a two part does not necessarily lead to elevated copper.

But it is certainly true that all additives will contain some metal impurities and some may have enough to be a problem. I have analyzed calcium chloride, for example, and show here what that adds:


Aquarium Chemistry: Purity Of Calcium Chloride ? Advanced Aquarist | Aquarist Magazine and Blog
http://www.advancedaquarist.com/issues/mar2004/chem.htm

Table 3 shows total elements added over 1 year when adding 16.2 ppm per day.