Magnesium and Potassium, we did just fine before, thank you!
If there is something about reef keeping that hasn’t changed over the few decades it has been practiced, it’s the passion to try out new things and the tendency to come up with new theories or observations that explain most if not all problems reef aquarists are having at any given time.
While sometimes these observations and experiences achieve little else than confusion among beginning hobbyists, most of the time aquarists’ observations really do move the captive coral reef aquarium keeping forward. Sometimes only a little, sometimes indirectly through increased communication but also in rare cases they can take aquariology to a completely new level. I’m sure no one will never forget hobbyists like Lee Ching Eng (1950s, live rock and live sand) and Peter Wilkens (1970s and 1980s, protein skimming, water chemistry, calcium supplementation, HQI lights etc) or some public aquarium curators like Jean Jaubert (1980s, DSB and plenum) and Walter Adey (1980s, refugiums and algae filtration). There has been very little contribution to reef aquarium keeping from scientific community, unless the researcher in question has also been a aquarist.
As said, many aquarists are very passionate about what they think will improve captive reefs but what is not yet accepted by the mainstream. And the mainstream nowadays is much more “main” than it used to be because the ratio of “independent thinkers” to others has declined rapidly as the hobby has gotten more popular. This creates friction in a community as the mainstream really wants to stay mainstream while at the same time you have separate pioneering groups of people on the sides who all are absolutely sure that if only everyone understood what they knew we would all have much better (as defined by said groups) aquariums. These are the kind of people that move us forward. Unfortunately it seems that while the ultimate goal of these groups is to get everyone to accept their methods and ideas their secondary objective almost always is the complete destruction of other groups. And the wars can be truly massive and bloody, like the epic battle DSB vs others that resulted in many brilliant aquarists leaving the online community forever. Some are quick and dirty like the ZeoVit’s attempt to gain foothold in mainstream. In the end the status quo won and the group was isolated in zeovit.com. It still in this day takes courage to admit that you are using ZeoVit in almost anywhere else. Note that these battles are never won 100%. For example, it is very rare to find the extremist DSBism in the wild today even though that group claimed glorious victory. The reason for this is that mainstream has one of the strongest weapons in their arsenal, common sense.
So, what all this has got to do with the two elements from the periodic table? Simply, both of these are fighting their way into the mainstream coral reef aquarium keeping and both display the common characteristics of pioneers vs. “the old way”. At this moment, the troops of magnesium are very close to claim victory as so many aquarists have purchased Mg test kits and forums are littered with questions regarding the best way of supplementing it. And as always, the original cult members have been very vocal about the issue, claiming deficiency in magnesium to be a reason for a wide range of anomalies, ranging from CaCO3 chemistry to fish health and everything in between. And as always, the majority has ruled that it is probably important to maintain NSW levels of magnesium and yes, it can affect coral calcification but at the same time, many of the other more fantastic claims are mostly exaggerated. Common sense.
Potassium, however, has still a long way to go. There really are no widespread interest in potassium test kits or supplements and although there are now some common sense injected in discussions (linking possible K+ sinks to the need of supplementation) it still seems to have most amazing effects on coral coloration and growth. A certain sign that there is still a lot to learn about potassium and its importance in coral reef aquariums.
What’s Grumpy’s take on magnesium and potassium? Once again, just plain old common sense. There was no single point of time in reefkeeping history that defined the moment between healthy, fast growing and brilliantly colored plating Montipora spp and plain looking, brown slow growing trash. You see, these are some of the properties of the two aforementioned elements claimed they would do if supplemented. On the other hand, both are absolutely critical elements of seawater and both have a wide range of biological roles so the awareness of even their existence will once again take the hobby a notch forward. While it might be a exaggeration to say that the obvious importance of these elements would be either pioneering work or groundbreaking discovery, it’s yet an other example how it’s the hobbyists who develop the science of captive marine ecosystems and no one else.
Sometimes I wonder why the process is so painful, though.