Young users and the Periodic Table: FYI

[Sk8r]

If you have never met the Periodic Table, it's a good thing to become acquainted with in this hobby. Understand that corals and fish both drink and breathe water, and that in that water (if tap) are numerous elements of that table that are Not Good For Living Things.

Ro/di filters remove everything but two hydrogens bound to an oxygen: water, in short. And you add salt. What is salt? What you use on your French fries is one sodium ion [qv] bound to one chlorine ion: NaCl.

Sea salt, the stuff you buy in buckets, is far and away a more complex white powder than NaCl. It contains such elements as calcium, magnesium, boron and molybdenum, selenium, iodine, etc, etc, in correct proportions as occur in the oceans---as water dissolves, yes, rock. Salt water is extremely aggressive about dissolving everything---rock, metal hose clamps, a cannon in a shipwreck: if it's reactive, seawater dissolves it. Gold and silver, 'noble' elements, do not react: so your gold ring is safe reaching into your tank. Your copper bracelet, not so much.

Water dissolving limestone from previous sealife is like kalk, or calcium dissolving in your tank: it's important part of that drink of water your corals and fish take. Calcium goes into coral skeleton; for bones; for the ability of muscle to move and contractile tissue to contract. And yes, for bristleworm spines and the little spicules angry corals leave in your skin.

If the calcium level of your water falls, the sea water goes after it where it can get it: it starts dissolving your coralline, your snail shells, even, yes, fishy bones---inside the fish---because the fish will leach calcium from its own bones to feed the muscle of his heart and gills.

So, yes, the Periodic Table is important to this hobby. In a sense it's the study of rocks, gasses, and fluids---all of which we use. And it's really worth a read-through, so you can understand what we mean when we say there's phosphate bound to your rock, or algae, and why a test won't show it's there. Or what happens to these elements when water evaporates [Hint: only the h's and the o's actually float away.]

As master of your tank, you're Master of a World, and an understanding of how it functions leads to smarter decisions :idea: and smarter buys and smarter questions.:dance:

 

[Allmost]

Excellent info.

I came across this table some time ago, thought Id post a link here for anyone interested, its a periodic table with concentration of Each element in NSW, kinda fun, and very informative if you are looking for something in specific

PS. there is a reason for periodic table being the format it is

http://www.marscigrp.org/ocpertbl.html

 

[chimmike]

here's one, how bout those tungsten carbide rings? My wedding ring is tungsten carbide

i know titanium isn't reactive, as it's used for tubing in chillers and heaters.

 

[Sk8r]

:lol: chimmike, you are safe: http://tungstenovernight.com/ Tungsten rings are non-reactive.

 

[Sk8r]

Neglected to mention an important concept: saturation. For instance, water dissolves calcium (kalk) powder quite handily---up to a teaspoon per gallon---and it can't dissolve any more than that. Extra kalk powder falls to the bottom of the bucket. If you put in MORE kalk, the extra powder begins to dissolve, until it reaches exactly the same saturation: 1 teaspoon per gallon. A not-too-great-coincidence is that this is what goes on in the ocean, too: ocean water carries that much calcium. It dissolves limestone and old shells and limestone sand until it has that much calcium in it, and then it stops dissolving limestone until something (fish, corals, etc) use it up. Then it dissolves some more. This is really convenient for reefkeepers. You actually can't overdose it, which is convenient for very new reefkeepers. It's one example of how neat water chemistry can be, and how steady a tank can be if you understand what's going on in this very narrow (but important!) aspect of chemistry.

Ocean water likes its salt at about 1.024-1.026, and critters expect that. Unfortunately salt WON'T reach saturation before you have some really pickled critters. So you can overdose salt: it's amazingly obliging about dissolving, unlike calcium. Evaporation is really a problem with salt---because of course salt itself never evaporates. No mineral ever evaporates. So if you've used tapwater, which has unwanted minerals in it, well, you see the problem, I think. And you see why it's important, once you switch over to ro/di, to do some water changes. It takes a while to clear out all that extra mineral content.