Edit: I just saw that you posted. I bet Joel has everything you need and I looked at another of your sponsors websites and found a link for you.
http://www.finsdepot.com/category/10772310Thanks for that link....definitely much more scientific and very informative! So far I have only gone through the PH section. It is nice that they actually cited sources.
What I did note seems to correspond to Randy's opinion:
"On some reef flats pH values have been measured to vary from as low as 7.8 to as high as 8.4 in a single 24 hr period (Yates and Halley, 2006). In some lagoons, pH has been measured to vary as much as 1 pH unit in a day (e.g., 7.6 to 8.6)" (Jury)
I suppose I am a bit confused about pH now that several of you are adamant that any kind of swing is bad. Like Joel say the "magnitude" changes sound very significant yet this article mentions that these changes are most common in highly diverse lagoons and reef flats. I assume this is where many of our specimens come from.
Later in the article it states:
"If the pH of our tank water is substantially high or low, it may have direct, negative impacts on many of the organisms in our tanks, not just the calcifying organisms."
I was kind of disappointed to not hear a more sound conclusion on the actual swing in home aquariums. This sounds like it is referring to strictly high and low pH rather than the natural fluctuation is refers to.
I apologize if I was rude before. I suppose it kind of struck me that Joel was so opposed to what I believed to be true for so long. I am still not totally convinced but I am glad a lot has been exposed even if it caused a bit of tension
I would also like to apologize to Bkreef for muddling this thread