benmatson":3vxji7za said:So, what kind of water did Bingman use to mix the salt with? It isn't mentioned, but seems pretty darn important to me. Especially considering the relative ion concentrations compared to NSW. Several of the manufacturers seem to be precisely and cooperatively wrong.
I understand clearly what Dr.Shimek is grasping at, however I disagree. Artificial ecologies are very complicated. If it was possible to eliminate the variations due to the different locations and environments that the separate tanks are kept in, and what Bingman says about SSW is acurate, then what Dr. Shimek says might be one of several good possibilities.
Let me pose this one for you. Suppose 'old tank syndrome' is caused by toxic trace metal build up and that synthetic salt mix is perfectly ok. It is very possible that the trace metals are from the source water that is filtered for use in mixing SSW. It is understood that RO membranes reject fewer impurities as they age. Also, DI units can, and do, leach trapped ions back into the water flow after they resins are exhausted. If the units are serviced regularly, trace metal build up is not an issue as only sweet water is used. However, not every aquarist replaces membranes and resin beads on a schedule that allows for some margin of error. In fact, many people post here that they service once the output water reaches some threshold level of impurity. So, the aquarist learning curve dictates that if using 1 megOhm water makes the cyano breakout and the corals shrink, then water quality must never be allowed to drop to 1 megOhm. That's fine and great, but what if using 2 megOhm water for SSW mixing leads to long term trace metal build up? The aquarist has little external motivation to maintain pure water because the short term effect on livestock is not measurable, even though his habits are poisoning his tank.
So . . . now we have two competing theories.
I would like to see more studies on synthetic sea salt. I also would like to see DI units with options for resistivity lights more like 15-16 megOhms instead 1 or 2. Anyway.
I doubt Bingman used anything but the purest RO/DI water for the testing, or it would be kind of silly to bother wouldn't it? :roll:
I'm not sure I follow your logic here. Shimek's test samples all had elevated levels of heavy metals, elevated to the point of being toxic to some reef creatures. Bingman showed that all the salt mixes tested had levels well in excess of NSW and well into the toxic threshold of some reef creatures.
That said, the question you pose is moot because the salts are already shown to not be acceptable. However salt isn't the only culprit here, just one of the contributing factors. Trace element additions are also to blame. Trace elements at any level other than trace are pollutants. Food also contributes trace elements (to a degree). The problem is the cumulative effect.
As for the RO membranes and DI cartridges, if you don't follow the basic guidelines mentioned in the instruction booklet that came with your unit, then I suggest you go back and re-read the portion on maintenance. Use a flush kit to rinse your membrane. Use a TDS meter to determine when your DI cartridge is in need of replacement. Contaminants are leached when the cartridge is spent AFAIK. If an aquarist is killing creatures because he/she can't follow simple maintenance procedures, then I suggest they find another hobby.
IMO



