Actually, I don't really care what caused the difference. I proposed the hypothesis that metals were the cause because it seems obvious. If you don't agree, fine. Propose another hypothesis and
test it. Or
test my hypothesis and disprove it. But do test it... All of the hooting and hollering obscures the real finding of the study, that being that other ASW did not kill the larvae. It doesn't make any difference to me, what the cause is. :eek2:
That some ASW has problems supporting delicate organisms was never a question as far as I was concerned. I have know for decades of the problems with some of these salts. However, I presumed, and I think a lot of other invertebrate zoologists presumed, that the
all ASW was equally nasty.
What I tried to show, and what I did show, was that some ASW appears to be as good as NSW within the constraints of the study. Frankly, as far as I am concerned, that's all that's necessary. Whatever the problems with some salts are, they are not my concern, they should be the concern of the ASW manufacturers. I really don't care if the problem is due to excessive heavy metals, or excessive farting by workers in the plant as the ASW mixture is being made.
Let them figure it out. If other folks have made salts that produce non-toxic ASW, then it is feasible and I now have a salt to use that is safe for delicate organisms in a reef tank.
I published the test simply so that other folks could also treat their animals better. You don't have believe the data and you don't have to act accordingly. However, I do, and I will.
If anybody wants to figure out why it occured, go right ahead. Enjoy.

However, such a determination is only going to be done with experimentation, it will not be determined by web surfing or argumentation. You are going to have to sit down design the tests, and then you are going to have to try to kill animals, because that is the only way you can be sure that materials are toxic or not.