Reconstituted Seawater?

[Dana Riddle]

Hi Randy,
What's the scoop on reconstituted seawater (made through the evaporative process)? There was at least one salt made through this process way back in the 60's when Rila brand was about the only brand available. I've heard that the residuals left after evaporation don't reconstitute in a manner that faithfully replicates natural seawater. Is this true? Thanks!

 

[Mark Gray]

following

 

[Randy Holmes-Farley Verified Community Expert]

Simple drying (evaporation) and adding water back will leave a solution that is very deficient in alkalinity and likely somewhat low in many metals that precipitate and will not redissolve. Calcium, in particular, but possibly magnesium, strontium, and trace metals that get caught up in calcium carbonate precipitation (such as iron, etc.). It might have a huge impact on certain trace metals, but I really don't know which ones or how much.

 

[Randy Holmes-Farley Verified Community Expert]

From an old post of mine (ignoring trace element issues):

This is the sequence of the main things precipitating from evaporating seawater:

1. CaCO3 and MgCO3 at about 50% liquid remaining (density = 1.14)
2. CaSO4 at 10% liquid remaining
3. NaCl at 3.9% liquid remaining
4. later comes sodium, magnesium and potassium sulfates, potassium chloride and magneisum chloride.

To make "salt", you can evaporate seawater down to between step 2 and 3, and take the liquid only

Then dry it down to between step 3 and 4.

The solids that precipitate are "salt" (mostly NaCl) and you discard the very concentrated brine (liquid) that remains before precipitating the things in step 4. That way the salt doe snot have a lot of magnesium, sulfate, or potassium in it.

 

[3mm3]

Looks to me like a great opportunity for a triton test experiment!

 

[Randy Holmes-Farley Verified Community Expert]

What's funny is Red Sea claiming:
http://www.redseafish.com/wp-content/uploads/2015/05/99438-Public-Aquarium-Catelogue.pdf

"Red Sea Salt has 86% of its components harvested by solar evaporation. "

Turns out that sodium and chloride constitute 86.3% of the mass of salts in seawater. It's not so impressive of a number seen that way. lol

They then say that they also get minor and trace elements from the seawater, but no quantitation.

 

[Dana Riddle]

Thanks. Glad to know my memory isn't totally shot. So my question is - Who uses Red Sea or DD salts for the successful maintenance of stony corals? Comments?

 

[Nano sapiens]

Thanks. Glad to know my memory isn't totally shot. So my question is - Who uses Red Sea or DD salts for the successful maintenance of stony corals? Comments?

I currently use 50% Red Sea 'Blue Bucket' and the rest Tropic Marin 'Classic' and have had good success. Interestingly, in Ken Feldman's article looking at possible sources of bacteria in newly made salt water, Red Sea was the only one out of the 6 brands (TM, Oceanic, IO, IORC, Kent, Red Sea) tested that had a 'not insignificant bacterial load' using a sterilized holding container. Presumably, this was due to some of the natural bacteria survived the drying process:

http://www.advancedaquarist.com/2011/3/aafeature

(Excerpt): Five of the six salt mixes (Red Sea excepted) displayed little bacterial contamination beyond the pure water control, and the bacteria populations fluctuated but did not consistently rise over time as might be expected if sufficient nutrients were available (cf. Fig. 13). Thus, there is no reason to suspect that any of these five salt mixes themselves contribute to the high levels of bacteria in the make-up saltwater of Fig. 13. Red Sea salt, on the other hand, does appear to bring with it a not insignificant bacterial load. Once again, there was little increase over 5 days, indicating that sufficient nutrients for growth were not available under these "sterile" conditions. What is so special about Red Sea salt? This salt, uniquely among the six mixes tested, is made, at least partially, by drying authentic seawater. Thus, it appears to retain some viable bacteria from the drying process. The other five salt mixes are prepared from mixing strictly chemical sources of the components. Overall, it appears justified to conclude that the significant populations of bacteria in mixed saltwater are a result of container contamination and not salt mix introduction per se.

Ralph.

 

[3mm3]

Thanks. Glad to know my memory isn't totally shot. So my question is - Who uses Red Sea or DD salts for the successful maintenance of stony corals? Comments?

I began using Red Sea back in 2009 for sps and clam tank with very good success. 4 years total before I had to move and tear the tank down. Currently I am mixing red sea and tropic marin pro.

 

[irischan]

Looks to me like a great opportunity for a triton test experiment!

Please remember to just take the liquid, leaving the precipitate.

 

[irischan]

I currently use 50% Red Sea 'Blue Bucket' and the rest Tropic Marin 'Classic' and have had good success. Interestingly, in Ken Feldman's article looking at possible sources of bacteria in newly made salt water, Red Sea was the only one out of the 6 brands (TM, Oceanic, IO, IORC, Kent, Red Sea) tested that had a 'not insignificant bacterial load' using a sterilized holding container. Presumably, this was due to some of the natural bacteria survived the drying process:

http://www.advancedaquarist.com/2011/3/aafeature

(Excerpt): Five of the six salt mixes (Red Sea excepted) displayed little bacterial contamination beyond the pure water control, and the bacteria populations fluctuated but did not consistently rise over time as might be expected if sufficient nutrients were available (cf. Fig. 13). Thus, there is no reason to suspect that any of these five salt mixes themselves contribute to the high levels of bacteria in the make-up saltwater of Fig. 13. Red Sea salt, on the other hand, does appear to bring with it a not insignificant bacterial load. Once again, there was little increase over 5 days, indicating that sufficient nutrients for growth were not available under these "sterile" conditions. What is so special about Red Sea salt? This salt, uniquely among the six mixes tested, is made, at least partially, by drying authentic seawater. Thus, it appears to retain some viable bacteria from the drying process. The other five salt mixes are prepared from mixing strictly chemical sources of the components. Overall, it appears justified to conclude that the significant populations of bacteria in mixed saltwater are a result of container contamination and not salt mix introduction per se.

Ralph.

Certain bacteria species produce offspring in spore form that revive when water comes again, just like seed. But one of these bacteria should be awared of is Clostridium difficile which is highly pathogenic. Thanks for your information and I am considering to stay away from Red sea salt...

 

[Nano sapiens]

Certain bacteria species produce offspring in spore form that revive when water comes again, just like seed. But one of these bacteria should be awared of is Clostridium difficile which is highly pathogenic. Thanks for your information and I am considering to stay away from Red sea salt...

Using a different salt is of course your prerogative. I use it for the reason that it has natural bacteria, which then are consumed by various reef dwelling organisms in the aquarium whenever I perform a water change

Ralph.

 

[Paul B]

This was tried a few times when the hobby first started with dismal results. I remember the tests then and it didn't work. I am not sure why sea water is not concentrated to like a quarter of it's mass and then reconstituted to save shipping weight. I think as long as you don't completely dry it,it should be fine, but Randy is the chemist and I am an electrician

 

[Rip Van Winkle]

I use seawater , not reconstituted

 

[Dana Riddle]

Yup, natural seawater. I had an unlimited supply 150 feet from the old house. Now I'm landlocked and, in some respects, starting anew in the hobby. Thanks for the input!