mps9506
Well-Known Member
A little more on calcium:
http://www.advancedaquarist.com/2002/3/chemistry
http://www.advancedaquarist.com/2002/3/chemistry
calcium over 500ppm
- Thread starter Scouter Steve
- Start date
One thing to remember is that there is no advantage in having a really high Ca++ concentration (at least when it comes to calcification). Quite the opposite, having both high Ca++ and alkalinity will make it increasingly difficult to keep both of them in the water column instead of inside the pumps and such.
Because "unnaturally" high alkalinity (unlike calcium) seems to help the calcification (which might be hampered in captive environments with higher than natural nutrient levels, for example) and provides some additional buffering against higher pCO2 found in many aquariums, I generally recommend having elevated alkalinity and NSW levels of calcium (3-3.5 meq/l and ~400 ppm Ca++).
IMHO, IME and YMMV naturally
Because "unnaturally" high alkalinity (unlike calcium) seems to help the calcification (which might be hampered in captive environments with higher than natural nutrient levels, for example) and provides some additional buffering against higher pCO2 found in many aquariums, I generally recommend having elevated alkalinity and NSW levels of calcium (3-3.5 meq/l and ~400 ppm Ca++).
IMHO, IME and YMMV naturally
Boomer
Reef Sanctuary's Mr. Wizard
Boomer on Vacation 
I spend hrs /day on Randy's chem forum he is gone till Aug 14. It is like everybody waits till he leaves and then WHAM threads/posts everywhere. The same thing happen last time he was gone.
Let me comment on BoomerD's analogy
He is talking about the LEP (Law of Equal Proportions). This law is based on ratios of ions in NSW and NSW only. As you know Ca++ is about 410ppm ann Mg ++ 1290ppm, so 1290 / 410 = 3.15 :1. It means that if the salinity of NSW is 35 ppt, 32 ppt or even 29 or 40 ppt, this ratio stays the same. If we look at the ratio of Na+ to SO4- (sulfate), Potassium to Barium or any ratio they will be the same whether the salinity goes up or down in NSW. This does and can not happen in a reef tank, way to much going on with different salt mixes, sup, foods added, top-off water, etc., etc..........BUT we try or should try to do the best we can.
They run thier salinity at 1.023 and has a calcium level of 450 and alk of 11. Now they might think hey 450 is a good number and the alk is in balance. But when you look at thier salinity level they are at the point of saturation and poisening
This would be a disproportional ion concentration, something we do no want. This is what you have heard called an Ionic Imbalance. Even though the Ca++ and Alk are balance, the other ions are not. Their normal ratios have shifted. Shifting such ratios affect other ions, which can make thing more difficult to maintain. It changes what we call their activity. The "wanting"of ions to go somewhere and do something. They can only go two places, stay in solution or leave solution, precip
.Example;
You get say 250 ml of RO/DI water and dissolve as much table salt in it as you can, until it is saturated. You now measure the amount of Na+ and Cl-. You now get the same amount of seawater and dissolve table salt in it until it reaches saturation. You now measure the amount of Na+ and Cl- . You will find out the seawater sample has more Na+ and Cl- in it. The other ions in seawater allow more NaCl to be dissolve. The other ions in seawater make other ions go more into solution. When you shift from normal or about normal ratios this activity changes for other ions making them to want to go somewhere and do something at a different rate, than form the normal ion ratios in seawater and we want to stay away from that if possible.
All meaning the closer we are to NSW the better off we are at keeping levels where they should be, not where you may want them to be
I spend hrs /day on Randy's chem forum he is gone till Aug 14. It is like everybody waits till he leaves and then WHAM threads/posts everywhere. The same thing happen last time he was gone.Let me comment on BoomerD's analogy
He is talking about the LEP (Law of Equal Proportions). This law is based on ratios of ions in NSW and NSW only. As you know Ca++ is about 410ppm ann Mg ++ 1290ppm, so 1290 / 410 = 3.15 :1. It means that if the salinity of NSW is 35 ppt, 32 ppt or even 29 or 40 ppt, this ratio stays the same. If we look at the ratio of Na+ to SO4- (sulfate), Potassium to Barium or any ratio they will be the same whether the salinity goes up or down in NSW. This does and can not happen in a reef tank, way to much going on with different salt mixes, sup, foods added, top-off water, etc., etc..........BUT we try or should try to do the best we can.
They run thier salinity at 1.023 and has a calcium level of 450 and alk of 11. Now they might think hey 450 is a good number and the alk is in balance. But when you look at thier salinity level they are at the point of saturation and poisening
This would be a disproportional ion concentration, something we do no want. This is what you have heard called an Ionic Imbalance. Even though the Ca++ and Alk are balance, the other ions are not. Their normal ratios have shifted. Shifting such ratios affect other ions, which can make thing more difficult to maintain. It changes what we call their activity. The "wanting"of ions to go somewhere and do something. They can only go two places, stay in solution or leave solution, precip
.Example;
You get say 250 ml of RO/DI water and dissolve as much table salt in it as you can, until it is saturated. You now measure the amount of Na+ and Cl-. You now get the same amount of seawater and dissolve table salt in it until it reaches saturation. You now measure the amount of Na+ and Cl- . You will find out the seawater sample has more Na+ and Cl- in it. The other ions in seawater allow more NaCl to be dissolve. The other ions in seawater make other ions go more into solution. When you shift from normal or about normal ratios this activity changes for other ions making them to want to go somewhere and do something at a different rate, than form the normal ion ratios in seawater and we want to stay away from that if possible.
All meaning the closer we are to NSW the better off we are at keeping levels where they should be, not where you may want them to be
BoomerD
Well-Known Member
First off, let me reiterate...this is NOT my analogy, just one that actually made some sense to me...Our old friend, MojoReef, (Mike O'Brien) is the author of that missive. It helped me to greatly understand the relation of the different ions in saltwater, and to understand how overdosing one, can either push something else out of solution, (like the snowstorms) or else, push your specific gravity out of whack...
I suppose it's kind of oversimplified, but it does (IMO) a good job of explaning things for those of us who aren't chemistry geeks...
I suppose it's kind of oversimplified, but it does (IMO) a good job of explaning things for those of us who aren't chemistry geeks...