Fatman
Fatman
I have found Randy Holmes-Farley only to be contradictory once (about iodine usage)
Where please show me.
I need show you nothing, as there is nothing to prove or disdparove. It is only taht at one time he made one recommendatioan as as time went on he changes his recommendations. call it growth or contradiction, whaat ever, it is adifference. Or opinions often change as I expect do his.
and can only remember finding fault in one small thing he wrote once and that was the statement that aragonite and crushed coral are both calcium carbonate and that calcium carbonate dissolved in marine water at a such and such pH.
Where you must have misunderstood what he said. Crushed coral is Aragonite. Thereis no misunderstanding. His aregument was that aragonite sand in a marine system does not dissolve at a lower ph than crushed coral. Crushed coral is very seldom aragonite. Crushed coral is nearly always undergone a change to calcite so its geometric structure is different causing it to dissolve at a lower pH.
Where as aragonite and calcium carbonate (crushed coral) dissolve at different marine water pH's
Different Aragonite, with different porosity, can dissolve at slightly different rates. i.e., aragonitic sand vs crushed coral etc..
Different aragonite with different amounts of different chemicals that accompany the aragonite, and might very well dissolve at different rates due to different accompanying. Porousity is not an issue, nor is the grasping at straws in relation to particle size. Given all things being the same except one being aragonite in its own unique geometric form and the other, calcite in it more stable geometric form or final form, as all aragonite will eventaully become aragonite as all allegedly become their most stable form eventually, the aragonite will dissolve at a lower pH.
But then there is the long argument that aragonite is a form of calcium carbonate, yes as is halite.
Halite !!! That is NaCl, Sodium Chloride .
Admittedly it was quite late and I wrote halite instead of Calcite, so whip me with a spagetti noodle.
What ! There is no argument at all anywhere on this
Calcite is CaCO3 and Aragonite is CaCO3 just different crystallographic morphs. There is also Hi-Mg Calcite and Low-Mg Calcite.
That is a laughable opinion that there is no argument. I dummied up what I previously wrote as most people do not know what a crystallographic morph is, sio I instead wrote different geometric structure or arrangement. The argument is still the same, as the two different calcium carbonates dissolve at different a different pH.
Well graphite and a diamond are both carbon, no one claims they dissolve in the same marine water pH or are of equal hardness. It is most typical for a chemical compound that has differing geometric arrangements in its structure but the same chemical formulas to have different physical properties and because of that dissolve at different pH's or have vastly different hardnesses or melting points etc. Not that any of this or that matters.
Yes that is true.
When I have difficulties believing something Randy writes I can generally go to a chemistry reference book or even a text book or two or three.
Maybe you do not understand what he is saying
Give me some examples or come to our chem. forum on RC and we will discuss it with Randy there. Then maybe it is just an option thing. You sound as if Randy is wrong, which is not a opinion. Yes he has been wrong at times but rarely. We all are wrong at times. But try not to come across here as if only *you are right.
Once again I need prove or show you nothing in regard to what I think about what or how Randy writes. I believe him the finest contributer in the aquatic chemistry field in the way of his posting of material for themarine hobbiest, but as I only have a minor in chemisrtry some times I must go back to the books to dispell some disbelief or misunderstanding I might have in something I read. Is that wrong? I do not believe so!!!! As far as participating at RC. No thank you I read from the site, but have no desire to participate in the mannerisms of that site.
I agree on the WC issue with you. There are many people that do very large water changes with little or no effect on corals , even sps's. Don W was doing ~ 100 % changes on his reef tanks and I use to do monthly 75 - 90 % changes for 20 years.
The calcium issue has been very misleading over the years, Chris Jury, a reefer and grad student, who's dissertation is on this very subject has come to the conclusion from his studies that Calcium levels over ~360 ppm does squat for coral growth and is controlled by pH and Alk, not Ca++ levels or other limiting factors. Meaning, if all *could be the same and one raised the Ca++ only from 360 ppm to 400 or 500 the corals growth rate would not change.