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

[jglackin]

I keep the jugs sealed, once I siphon off the clear kalk water, but not in the mixing barrel. I have never heard this. Will this somehow affect my pH? My pH in my tank is pretty steady at around 8.25.

[jglackin]

Thanks, everyone, since I have added the mg, my cal and alk have been rock solid.

[jsdancer]

Hey guys,

Since keeping my reef tank I have only ever added a two part solution 3 times a week and dose kalkwasser once per week.
I have never added Mg.

I have seen the following:
1. good coral growth
2. nice coloration
3. abundant coraline algae growth


Only one thing that is slightly different
1. in some of my sps's, their polyps are not extended during the day, but they are during lights out.

I would like to try and add Mg and see what may be different.

I will let everyone one within one month.

Juan

[Aquarist007]

Originally posted by jsdancer
Hey guys,

Since keeping my reef tank I have only ever added a two part solution 3 times a week and dose kalkwasser once per week.
I have never added Mg.

I have seen the following:
1. good coral growth
2. nice coloration
3. abundant coraline algae growth


Only one thing that is slightly different
1. in some of my sps's, their polyps are not extended during the day, but they are during lights out.

I would like to try and add Mg and see what may be different.

I will let everyone one within one month.

Juan

what is your present level of magnesium?

[jsdancer]

I have never added Mg to my tank and have no test kit for it either. I will head to my reliable lfs store and pick some up.

I would like to see if by adding Mg to my system if things will be better and improve the corals growth potential.
I know. I know if it ain't broke why fix it. But if Mg is an important element then it has to be something that I should consider.

Juan

[Aquarist007]

Originally posted by jsdancer
I have never added Mg to my tank and have no test kit for it either. I will head to my reliable lfs store and pick some up.

I would like to see if by adding Mg to my system if things will be better and improve the corals growth potential.
I know. I know if it ain't broke why fix it. But if Mg is an important element then it has to be something that I should consider.

Juan

the saying here should be don't dose before you measure--not only for mag but for anything you are going to add to your tank.



the optimal level for magnesium should be 1300 ppm

Measure your existing level, decide on a product and use the chemistry dosing calculator in the reef chemistry forum.
Also head the daily max that it will provide you

http://reef.diesyst.com/cf/chemcalccf.html

[daughertyja]

what is the highest you want your mag levels to be either my test kit is bad or i added way to much mag my level is at 2000

[melev]

That is much too high. On average, it should be three times the calcium level. For my tank, I try to keep it between 1300 and 1400ppm.

What kit did you use? Do you dose Magnesium? If so, don't dose it anymore. It'll take a long time for it to drop, but it will drop.

[daughertyja]

my test jit is a redsea one. i do dose the two part mag from bulkreef. i am going to take a sample to the lfs. i see no ill effects of it. but what i do see is the hair alage all is comming off the rock very easy almost falling off.

[melev]

That's very likely, as super high Magnesium can do that to bryopsis and GHA, as you noted.

However, Magnesium isn't usually considered a two part dosing system, other than mixing Magnesium chloride and Magnesium sulfide together with RO/DI water to create a bottle of solution.

Regardless, you don't need to dose it for a while now.

[daughertyja]

i have no plan on adding more until i figure out if is is my test kit or me not paying attention to it. the mag that i have is the cloride and the sulfate mix. thats for your help melev

[kellyslater.it]

i keep my alk at 4 calcium 360 mg 1200,it is enaugh for corals grow,superior level mean more co2 and a lower ph.
under ph 8,2 becomes more difficult for cells to expel protons (H +) that are produced in excess during calcification.

[five.five-six]

that is right in line, I might bump the ca up to 420, but you will need to get your MG above 1400 first

[kellyslater.it]

with low parameter i have best results for growt and colors,i don t use bailling.

[Mr.leee]

Originally posted by jglackin
Care to elaborate?

when kalk is mix with air it becomes unusable (hint you will see white fakes floating everywhere)

[jobu28]

I have a question for you guys that no one has been able to answer so far. I have a 34g Solana with mainly softies. I have upgraded to a MH to try SPS and LPS. So I have been testing regularly for awhile. I basically have to dose(ions by seachem aquavitro) every day to keep my Mg over 1250. My alk is good and my ca is a little high, usually close to 480-500. I never had to dose ca except for the past few weeks as i added a clam. Any thoughts on why i need to add so much Mg?

[melev]

It takes a ton of Magnesium to bring it up to 1300-1400ppm. I personally like to keep it around 1400ppm for my reef.

Using Jdieck's magic calculator: http://reef.diesyst.com/flashcalc/flashcalc.html

I input 34g (tank size), current Mg at 1250 and desired Mg to 1400ppm. I selected ESV's Magnesium supplement since I know that is something you can purchase easily enough, and it stated you needed to add 510ml or 17.2 oz to bring it up.

The good news is that once it is up, it stays there for a long time. Keep testing regularly, but you may find you only need to dose it every couple of months to keep it where it needs to be, if you keep Salinity, Calcium and Alkalinity at target levels.

That calculator is very helpful, so bookmark it and use it often.

[jobu28]

So do you hnk i just need one huge dose? I test it in the morning and its low. I add a capful or so of the Ions and its around 1400. Two days later i test and its around 800? I use elos kits and have had my results confirmed by my LFS.

[melev]

Well, I've not used that particular product so I don't know how concentrated it is, but the fact is that once Mg is up, it tends to stay up for weeks on end. For it be low, then up, then low again a couple of days later seems a little unusual.

Keep in mind that Mg test kit results can be skewed significantly. I think it was Bertoni that told me he tests Mg three times in a row, then averages out the three results to get an accurate measurement that day.

A big dose of Mg won't hurt your tank.

[Aquarist007]

I use plain old epsom salts from the drug store to raise magnesium levels. I get 2 lbs of it for 5 bucks.
I raised it 3 months ago to 1400 ppm as to Marcs suggestion and have not had to touch the level since

[Lyfey]

In my 75gal DT/ 30 gal sump, roughly 89 gallons total water volume. I used 1 cup of epsom salts disolved in 3-4 cups RO/DI and it raised my MG from 1250 to 1300. Using these calculators are difficult because they dont support brightwell suppliments and who knows how many grams of epsom salts? I dont have a scale for that. They should have a more "user friendly" calculator with common measurements. Just my expirience for raising MG.

[melev]

Your method isn't a balanced one, if you are trying to match water chemistry. You need Magnesium chloride to go with the Magnesium sulfate you have. Just taking a cup of Epsoms Salt alone is unbalanced, and we know it is all about the ions. Following RHF's Recipe #2, I use 7.25 cups of Mag Flake and .75 of a cup of Epsoms Salt carefully mixed with 1 gallon of RO/DI water.

I use Jose's calculator. If he needs to add Brightwell's additives to it, ask him.

[Lyfey]

What exactly does the "balance" issue unbalance? I understand doing it this way is unbalanced, but all I had was the epsom salts. When a system is "unbalanced" what happens?

[melev]

I'd have to refer you to Randy's Magnesium article to provide the facts. Off the top of my head, Epsoms Salt will definitely affect salinity when a lot of it is used.

http://reefkeeping.com/issues/2006-07/rhf/index.php

[Laddy]

I disagree with respect to raising Mg levels in one big addition.

I've always tried to keep my levels north of 1300, with an average around 1350, by mixing up mag chloride with my RO/DI water and letting the mixture get added when the top-off kicks on. It's dump and forget, to a certain extent, and it really prohibits large swings--depending on evap and pump strength.