1. Calcium, Alkalinity and Magnesium
I really just started this thread/post as a way to assist some of our newer members; also I have noted a serious lull to befall the forum. Times are notably tougher and disposable income isn't so disposable any longer. If you're already bored please skip ahead to section 1.
We are water keepers; everything else in the tank that survives or lives is simply a bonus of our hard work. That's what we do; we take care of our water, priority number 1. If it comes to a point where we can fully control the water parameters in our tank, we are further likely to add something to it, at the end of the day we'd like to have a few prized corals or a few prized fish that sport or pride our passions within the hobby. Some reefers, fish keepers have different goals and others may just enjoy the equipment wow. Whichever category you categorize yourselves in; there are mainly 4 different types of fish tanks we are able to combine or find success in, many people have different preferences, however the water quality needs to be maintained in order for the relevant goals we would like to attain within our tanks, to be reached.
Here is a video that has helped me understand, a lot easier, how the Calcium, Alkalinity and Magnesium works within our tanks:
Section 1
Mg = Magnesium(Assists in maintaining Calcium and Alkalinity Levels)
Ca = Calcium(Building Block)
Alk - Alkalinity(Building Block)
Calcium and Alkalinity are the basic building blocks of a reef tank, if any of these remain at low levels the coral in your tank will tend take strain. Raise them high enough and the same dire consequences will take place, adjust them too quickly and you are likely to wipe out your tank. Magnesium maintains the high levels of Calcium and Alkalinity so there is no precipitation of the Calcium into something that cannot be used by coral. Coral skeletons are much like ours but have specific external requirements of the surrounding water. Salt water isn't just salt water, there is a lot more to it. There is also various portions of the ocean that have different parameters than other specific areas of ocean water. And these can change on a daily basis.
General Ocean and Aquarium water Parameters:

Cited: Reef Aquarium Water Parameters by Randy Holmes-Farley - Reefkeeping.com
Here are the General specifications to Ocean Water:

cited from: http://www.soest.hawaii.edu/oceanography/courses/OCN623/Spring 2015/Salinity2015web.pdf
I would love to add further to these posts by those that know more than I do regarding the relative parameters at hand and would like to leave this space as forum space so if a new reefer comes to find this post, the meat of the information required to be that much more successful within the hobby can be obtained quickly and within the first few pages.
I will be adding, editing to this post and will reserve the next few posts to allow for a basic Q and A of the aforementioned water parameters. I do not claim to be any sort of Doctor, Professor or any sort of Marine Biology student, I am just concerned as were with the amount we should know before dipping our feet into the hobby.
Please be aware that I will attempt to amend and add to these posts daily as time permits. Feel free to ask away.
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