Let's talk about Alkalinity, Calcium and Magnesium in an SPS Tank

[bradleyj]

Joe, I dose with Seachem Reef builder also when my alk gets low. Can you add this when you make your saltwater for a waterchange ? like you do with mag? Or is it better to just mix with ro/di?

[JB NY]

Originally posted by bradleyj
Joe, I dose with Seachem Reef builder also when my alk gets low. Can you add this when you make your saltwater for a waterchange ? like you do with mag? Or is it better to just mix with ro/di?

Yeah you can.

This is what I do when I do a waterchange. Fill up the bucket with ro/di water then add the salt. Then add whatever additives I need to get that water the same levels as is in my tank. for the alk and calcium additives I still mix them in a cup of ro/di water before adding it to the new saltwater.

[SDguy]

But only if you are trying to raise the alk of the new water to bring it to an acceptable level. Trying to add extra, so as to raise your tank alk this way could very likely cause a precipitation effect in the new water. I'm sure this is not not Bradleyj meant, but I wanted to just clarify in case anyone reading this thought this way.

BTW Joe, I'm with you on the Magnesium. I found (in this tank and my previous tank) with Mg at 1100ppm or so, I could NEVER get my Ca above 360ppm.

[JB NY]

Originally posted by SDguy
But only if you are trying to raise the alk of the new water to bring it to an acceptable level. Trying to add extra, so as to raise your tank alk this way could very likely cause a precipitation effect in the new water.

Good point.

Originally posted by SDguy
BTW Joe, I'm with you on the Magnesium. I found (in this tank and my previous tank) with Mg at 1100ppm or so, I could NEVER get my Ca above 360ppm.

Yeah so many calcium problems could be fixed faster if people would test their Mg more often. I test mine about as much as I do my calcium.

[capn_hylinur]

Originally posted by JB NY

capn_hylinur Sometimes if you are pushing your ca reactor too hard it can cause lower tank pH. The only suggestion is to try and dose some kalk at night. I used to mix a teaspoon of kalk with a little ro/di water and just tossed it in the sump. I did that a few years back when I was having large pH fluctuations. The ultimate solution was to get a different ca reactor that didn't have to work so hard, but that's another story. [/B]

thanks JB NY but I am not running a calcium reactor. For the last year I have been using Randy's article on Solving alk and pH problems. I am due for a water change---maybe I should start over using the b-ionic two part system and try to bring stability back to the pH.?
Is a big flucuation in pH a problem for SPS corals or should it just be ignored and worry about alk calcium and magnesium(those are very stable right now)

[Sk8r]

To my knowledge, corals don't like rapid change in any parameter. I'd try to eliminate any bounce in anything to do with water, though I can't point to any specifics regarding ph. I'd *think* that it might affect the condition/penetrability of their 'skin,' making it more or less vulnerable to bacteria, etc, but that's only guesswork. The more 24/7 any 'good' situation is, the more corals are going to settle down and do their thing: I think that's safe to say.

[piercho]

Does anyone have concerns over the rise in sulfate when adding epsom salt (MgSO4) to bring up Mg? I think some of the hobby Mg additives may also be mainly MgSO4. For people doing a 1100 to 1400 Mg bump with epsom salts, you could be getting a dramatic rise (44%) in SO4 levels. Magnesium Supplements, RH Farley

[JB NY]

I would say if you only use epsom salt that sulfate would be a concern. I've never used it for that reason. I've used ESV liquid mag in the past. But will be trying out Magnesium Chloride in the future.

[JetCat USA]

Originally posted by JB NY
I would say if you only use epsom salt that sulfate would be a concern. I've never used it for that reason. I've used ESV liquid mag in the past. But will be trying out Magnesium Chloride in the future.

Regular water changes help control the ionic imbalances caused by just using the Epsom salt. you run into the same issues with the use of just MgCl with it being the chloride ions that get imbalanced. the best is to mix 3 parts MgSO4 to 5 parts MgCl.

[Sara B]

Great Thread! It reminded me to quit wasting my time trying to dose Alk and Calcium and concentrate on the Magnesium first. I order Kent Tech M by the gallon jugs! Does anyone else have good luck with Tech M or is there something else better out there?

[JetCat USA]

buying your own MgCl and MgSO4 is much cheaper long term if you have allot of water volume.

[Sara B]

Originally posted by JetCat USA
buying your own MgCl and MgSO4 is much cheaper long term if you have allot of water volume.

Thanks. I will have to re-read Randy's recipe and try to locate the ingredients locally as I know it will save me some money. I still have 2 gallons of Kent left, but with 500 gallons of water, it will go quick enough.

[IPT]

I am really new to all of this and learing day by day. This site is awesome! I understand Joe that you and many other keep the Alk a little lower and Ca a little higher - relatively speaking. Does anyone do the opposite? I seem to recall reading something about "farming" that recommended higher Alk (~12, and lower Ca ~320) for faster growth. It was possible that color may be sacraficed though. Anyone experience that? Does it make sense to do that a while for someone with lots of frags and then slowly transition to the inverse as the tank matures and colonies grow? I don't know, just a thought since this is a disussion I thought I'd throw it out there. I don't have enough experience to comment but hopefully some of you do.

[piercho]

JetCat, I had to hunt for the basis of your 3:5 MgSO4:MgCl ratio recommendation. Improved 2-Part Supplement Article; Farley: Recipe #1, Part 3A. But to get the desired final ion ratio (table 2), I think that you also have to be using the 2-part additives alone to keep Ca and carbonate up? If you are using limewater and a calcium reactor instead of the 2-part additives for Ca and carbonate, wouldn't you want to use a 1:10 MgSO4:MgCl ratio as Farley recommended in the origonal Mg supplementation article? I'm not clear on that point.

I'm off to YellowKnife Canada for 10 days and hope to catch a fish or two. I hope you guys keep this up.

[JB NY]

Originally posted by JetCat USA
you run into the same issues with the use of just MgCl with it being the chloride ions that get imbalanced.

What does a choride imbalance do? I thought the ESV liquid Mg was magnesium choride.

Originally posted by IPT
I seem to recall reading something about "farming" that recommended higher Alk (~12, and lower Ca ~320) for faster growth.

I don't think that would work. Higher Ca almost always equals higher growth. Acros in my tank grew like grazy with high Ca. with my Ca at 500 and Alk at 8 dKH I was able to pull a good 30 frags (min size 1 1/2") a month out of my 180.

[naka]

Another tip in raising ALK is to raise it SLOWLY. I see too many people trying to raise ALK overnight using Part B, baking soda, etc... Instead of using baking soda to raise it, I like to drip Kalk overnight. Then test your water after 24 hrs, not very next morning.

[JetCat USA]

piercho

in order for a CaCO3/CO2 reactor to dissolve Mg the pH would have to be considerably lower then we run (to the point it would mud the media pretty quickly) therefore any Mg that's in your media is coming out as a precipitant and does little for helping keep the tanks levels up. back yrs ago we all used to add a few handfuls of Dolomite to the reactor but it never did any good.

the 3-5 ratio is balanced, i don't see why it would then be unbalanced just because you use a CaCO3/CO2 reactor or Kalk, if that were true, then using the reactor or Kalk without a Mg supplement would also be throwing your system out of ionic balance, i think most would agree that's not happening.

Joe

it's my understanding that one ionic imbalance is just as bad as the other. with that said if you have to use just a single additive the imbalance is lesser by the use of MgCl then the use of MgSO4 for the same ppm increase for a given volume of water.

[IPT]

Science is often behind the real world and lab testing results are not always easily transferable to reality. That being said, in Randy's artical (http://www.reefkeeping.com/issues/2004-05/rhf/index.php), unless I am misunderstanding, it seemed that raising alkalinity above nautral seawater levels had more effect on growth rates than raising Ca. That was a sterile environment - and there was no mention of coloration or any other measure besides calcification. I have held my Alk higher and Ca a little lower and this thread is making me reconsider that philosophy.

[piercho]

Sarah,
2-Part Solution, an RC sponsor, sells the dry chemicals to make Randy's Ca/Carbonate/Mg additives. They have the chemicals either in bulk or in pre-portioned packages to make standard solutions of known concentration. There is also a calculator on their website that will assist to figure out the dosing volumes of the standard solutions. If I knew another site offering the dry chemicals in conveniant volumes I would point it out, but the only one I'm aware of is 2-Part and I have used them.

JetCat, I'm saying that I think that the 3:5 ratio winds up being balanced (with respect to Cl and SO4) only if you have Na and Cl being added from the other parts of the two-part solution. To get the final ion ratios in table 2, I think you have to use all three parts. If you are using limewater and/or a calcium reactor instead for Ca and carbonate you aren't adding the Na and Cl that would be added if you were using 2-part. So when you use part 3A for Mg, your chloride and sulfate ratios increase with respect to the other major ions. And the sulfate ratio could climb quite steeply. For people not using the Ca or carbonate 2-part components, I would think that you would want to use mostly MgCl to boost Mg, as Randy said in the origonal Mg supplement article.

That is how I figure it, but I'm no chemist that is sure. And it seems if you exchange enough water frequently enough, the major ions should stay pretty much in line anyway. At least thats what I took away from the Randy's Mg supplementation article.

[stony_corals]

Solbby, is the Mg that is used taken from the water column or from food?

If you are using MgCl and MgSO4 to raise Mg levels, you shouldn't use the formula that Randy uses in conjunction with his two part. You should use 7 1/4 cups of MgCl to , I believe, 1 3/4 cups MgSO4 to a gallon of water. The Mg formulation when used with the 2 part is balanced when used with the two part, otherwise, it's unbalanced.

I'm slowly trying to raise one sys to the "Italian" levels 1500 Mg, 500 Ca, 10-11 dKH, do we'll see how that goes with sps....

[capn_hylinur]

Originally posted by Sara B
Great Thread! It reminded me to quit wasting my time trying to dose Alk and Calcium and concentrate on the Magnesium first. I order Kent Tech M by the gallon jugs! Does anyone else have good luck with Tech M or is there something else better out there?

Sarah, probably you measured your mag first---what is the reading. I dosed with Seachem mag for about a month every other day--the reading has been 1350 and stayed there--I haven't dosed mag for at least 3 weeks either and it is staying there. I think once you get the mag up to 1300 it stays there without alot of dosing.

[Sara B]

Originally posted by capn_hylinur
Sarah, probably you measured your mag first---what is the reading. I dosed with Seachem mag for about a month every other day--the reading has been 1350 and stayed there--I haven't dosed mag for at least 3 weeks either and it is staying there. I think once you get the mag up to 1300 it stays there without alot of dosing.

Dosing daily I have raised my Mg from the low 1100's to 1250. I still have low Alk at 6.1dKH and CA is at 470. My other system has Mg at 1155, Alk at 7.7dKH and CA at 400. I like to dose slow rather than add the large amounts suggested by the calculators. I'll continue to work on it and try the two part when I'm out of Tech M. I'm also going to get some new test kits as well since these are a bit over a year old (Saliferts).

For my other additives, I use Turbo Calcium for increasing the CA in my new saltwater. I dose Ca in the tank with 400 Ca and I don't dose the other tank as it holds typically at 450 with no additives. I also have the Warner Marine 2 part and use that for daily Alk and Ca dosing.

[DaveJ]

Interesting thread.... and I want to get input that I think others may find useful, as I would.

When y'all talk about stability, please define that as ranges per day.

Ca - +/- x ppm
Alk - +/- x dKH or ppm
Mg - +/- x ppm


Let me tell you why this is important for me... when I hear stable, that means steady consistent levels. Calcium runs 420 all the time for example. Or Alk is 9.5 all the time....

However, in our tanks, that constant value is almost impossible. Daily dosing say 70ml of Alk solution (two part) is to offset the .3 or .4 drop in dKH (15-20 ppm) per day. If you do that all at once, its not 'supposed' to be hard on critters. .5 is generally the acceptable daily change amount. However, by having to dose to adjust that level back up to your 'ideal' value, its by definition not stable.

See what I am getting at?? So please define stable and put some values attached to it.

[Sk8r]

Mine used to swing 10 pts a day cal, alk pretty stable due to dosing buffer via topoff, and I still had good growth, good PE, not so great color. Well, rotten color. Ushio bulb, which is another issue.

Now with a kalk reactor, I'm staying right at 9.3 alk and 420 cal for weeks on end. I can say this supplementation works with a 54 g tank with small coral 'draw' on calcium. It remains to be seen how it holds up in conditions of more demand---also I don't know what the cutoff is between what kalk can do vs when you start needing a calcium reactor.

The swing didn't seem to hurt too much, however, just with acropora aculeus and particularly montipora species, and ac. valida. The bali slimer seemed to be a little less happy with it.

[chessmanmark]

I don't know how to insert a quote but I don't think this was responded to-
"Is a big flucuation in pH a problem for SPS corals or should it just be ignored and worry about alk calcium and magnesium(those are very stable right now)"

I think ph would be the first thing you need to test for and look at. I have most of my books in storage right now or I'd look up Anthony Calfo's quote on this. His point is so clear because of his eloquence. Now if I remember how he said it (not sure of the numbers involved), however his analogy on ph was the difference (perhaps in a point difference in ph?) was comparable to sitting on a nude beach in Miami naked and then instantly being transported to the frozen artic, still naked. Don't underestimate the importance of ph.