Calcium dosing they say?? .....WHAT!....HOW do I do this?

[Orm Embar]

Hopefully the Red Sea materials work out for you, they're very popular. Since I have a chemistry background, it'd be professionally embarrassing if I didn't make my own.

If you decide you want to make your own at some point, it's actually really, really easy. Most of us that do water changes don't dose magnesium, since it's not consumed very rapidly by the organisms in the tank. So that leaves calcium and alkalinity which absolutely must be dosed in some sort of fashion unless you've a system devoid of corals. All you need to do this is calcium chloride and either sodium bicarbonate (baking soda) or sodium carbonate (washing soda), or both.

The calculators on BRS's website will work regardless of whether you bought the chemicals from them. Since both calcium chloride and sodium bicarbonate/carbonate are food ingredients, I'm betting you won't have any trouble getting them in the UK.

As "Mom" notes, Randy is the godfather of DIY reef chemistry. Here is his quite-famous-among-reefers original article on which the BRS 2-part solution calculator is based. Even if you don't plan to make your own solutions, you should definitely read his "Calcium and Alkalinity" article so that you have a good understanding of what you're dosing and why. Finally, you should take a look at his "Solving Calcium and Alkalinity Problems", which gives you some information about correcting imbalances in these components.

This - Randy's articles explain everything. The short version - calcium and alkalinity are generally dosed in balanced amounts, since corals generally use roughly as much calcium as they do alkalinity. Hence, the term "balanced" additives. There is some calcium drift, but in general if you test alkalinity and use that as a marker for both calcium and alkalinity consumption, then you can test calcium only monthly to make sure that you are on track with balanced additives. Mag is tested and dosed separately, generally.

Kalkwasser, 2 part, and (newer but what I use) 1 part with calcium formate are all fine. I have a jug of Randy's sodium carbonate alkalinity as well (and a jug of calcium carbonate, too).

I will add - I have a chemistry degree as well (only a Bachelor's, though), and I'm sure as heck not making my own additives! :-D

 

[Emma01]

This - Randy's articles explain everything. The short version - calcium and alkalinity are generally dosed in balanced amounts, since corals generally use roughly as much calcium as they do alkalinity. Hence, the term "balanced" additives. There is some calcium drift, but in general if you test alkalinity and use that as a marker for both calcium and alkalinity consumption, then you can test calcium only monthly to make sure that you are on track with balanced additives. Mag is tested and dosed separately, generally.

Kalkwasser, 2 part, and (newer but what I use) 1 part with calcium formate are all fine. I have a jug of Randy's sodium carbonate alkalinity as well (and a jug of calcium carbonate, too).

I will add - I have a chemistry degree as well (only a Bachelor's, though), and I'm sure as heck not making my own additives! :-D

So I should dose all 3 separately?
My additives are coming tomorrow and I want to be certain I’m doing it all correctly.
Mg-1120
Ca- 340-370
KH- 7.6 (variance of approximately 0.1 every day)

My plan was to.....

• Test the ca, mg, alk and use a dosing calculator to establish how much I need to add to get to ‘desired levels’
• I’d then add slowly throughout the day until ‘desired’ is achieved
• Test thereafter every second day to establish how much is being used and dose thereafter, if needed.
• My weekly water changes...... I guess I would do them as normal, check parameters after hour or so. And add reagents (ca,mg,alk) if required.

Does this sound like a good plan to you all????

Thanks
Emma xxx

 

[ckalupa]

Emma - When you use the dosing calculator it will likely show you that not all of the additives should be dosed in one day - taking up Calcium/Alk/Mg from lower numbers should be spread out over a few days to weeks if really moving the numbers.

You would not want to take ALK from 7.5 to 11.5 over even a few days as that is a pretty drastic move. Even the Mg - if you want to move from your present 1120 to 1350 - that needs to happen over some days to keep your frags happy. Nothing fast makes a good outcome in this hobby. And something you change today may not show up as angry corals for a couple weeks is what I have found.

 

[Randy Holmes-Farley Verified Community Expert]

Are you speaking to her specific tank? I drop a good bit of calcium every day.... but I have SPS colonies/frags. My dkh drops about a point every two days. Say, from 8.8 to 7.8.

Any tank. A 46 ppm drop in calcium in one day MUST be accompanied by an alk drop of about 7 dKH per DAY.

 

[BestMomEver]

Any tank. A 46 ppm drop in calcium in one day MUST be accompanied by an alk drop of about 7 dKH per DAY.

So if I drop dkh of .5 a day, what would typically be the appropriate drop in calcium?

 

[Emma01]

Any tank. A 46 ppm drop in calcium in one day MUST be accompanied by an alk drop of about 7 dKH per DAY.

Must’ve been a test error. Re-checked today.
I’ve built a trend of 5ppm/day use for calcium
And KH- 0.1ppm/day.

I’m planning to slowly bring the Ca up to about 400-420 over the week and attempt to maintain it at these Parameters.
Same for KH- slowly bring up to about 8.0 over the week.
Magnesium- same. Slowly bring up over the weeks.

Will magnesium supplementing increase calcium though?

 

[Randy Holmes-Farley Verified Community Expert]

So if I drop dkh of .5 a day, what would typically be the appropriate drop in calcium?

About 3-4 ppm per day.

 

[Randy Holmes-Farley Verified Community Expert]

Will magnesium supplementing increase calcium though?

Nope. That's not a concern.

 

[Emma01]

Nope. That's not a concern.

Great. Thanks

 

[Randy Holmes-Farley Verified Community Expert]

You're welcome.

Happy Reefing.

 

[Emma01]

You're welcome.

Happy Reefing.

You too ! We’ll see how it works out and Hopefully I don’t add too much
Thanks

 

[Orm Embar]

My understanding is that alk shouldn't be corrected faster than 0.5-1 dKH per 24 hours; I like the 0.5 dKH/day maximum.

Here's an article by Randy - https://www.advancedaquarist.com/2002/11/chemistry

 

[Dkeller_nc]

I will add - I have a chemistry degree as well (only a Bachelor's, though), and I'm sure as heck not making my own additives! :-D

Why not? It's pretty easy to do, and the calculations are pretty straightforward. And you don't even need to do any calculations if you're measuring by volume ala the instructions in Randy's article (and on BRS's site).

 

[MARK M. DAVIS]

Recommendation. Hanna vials need to be cleaned very well. Get a 10ml syringe and don’t rely on painted vial line. Sample size is 0.1 ml so any slight inaccuracy is exaggerated in your reading. Do brs 2 part. Use their calculator. Dose 1/10 strength. Measure and adjust your dosages. Creep up to your endpoint without rushing. 380 on calcium isn’t that bad and your population and consumption is still manageable.

 

[Orm Embar]

Why not? It's pretty easy to do, and the calculations are pretty straightforward. And you don't even need to do any calculations if you're measuring by volume ala the instructions in Randy's article (and on BRS's site).

I suppose I could; I haven't done the calculations for a long time and would rather pay a little more for a premeasured product (or use a recipe) for convenience

 

[Emma01]

My understanding is that alk shouldn't be corrected faster than 0.5-1 dKH per 24 hours; I like the 0.5 dKH/day maximum.

Here's an article by Randy - https://www.advancedaquarist.com/2002/11/chemistry

A very interesting read. Thanks for sharing!
I was not aware that by adding just calcium supplement, will bring KH down, and vice-Versa- by adding KH alone it will bring down calcium levels Now it makes sense that they should be dosed together.
It does say in ‘equal parts’ though. What exactly does that mean?- in the same ‘quantity/mls’ ?

I’ve got the Redsea additives coming today A, B, C (in separate bottles)- not combined.
So to make any changes to calcium, id need to make changes to KH too??

 

[Martin Kuhn]

Your tank consumes both. Ca and Alk

As you dose only one component it’s very likely that
- this one gets röntge ok level and drops from there
- the other will drop immediately
as a result of the tanks consumption of both (not by dosing the additives themselves!)

 

[vetteguy53081]

If youre doing regular water changes with a good quality salt, you can minimize any need for dosing

 

[Dkeller_nc]

A very interesting read. Thanks for sharing!
I was not aware that by adding just calcium supplement, will bring KH down, and vice-Versa- by adding KH alone it will bring down calcium levels Now it makes sense that they should be dosed together.
It does say in ‘equal parts’ though. What exactly does that mean?- in the same ‘quantity/mls’ ?

I’ve got the Redsea additives coming today A, B, C (in separate bottles)- not combined.
So to make any changes to calcium, id need to make changes to KH too??

No, not necessarily. The "equal parts" bit has to do with how calcium and alkalinity are consumed by corals to make aragonite coral skeletons. Specifically, they're making calcium carbonate (chemical formula CaCO3), so the coral is "consuming" one molecule of calcium and one molecule of carbonate ion to make one molecule of calcium carbonate. Most recipes and pre-made products are therefore designed so that there's an equal concentration of calcium in one part to the carbonate concentration in the other part. In that way, the aquarist can just measure equal volumes of both parts, and know that they've added "balanced" calcium and alkalinity.

On the other hand, if you calcium level is too high, you can simply dose the alkalinity part for a while without the calcium component to let the "extra" calcium be consumed. Similarly, if your alkalinity is too high, you can simply dose calcium for a little while and let the alkalinity fall until you reach your desired range, and then dose both parts to maintain the concentration that you want.

One additional caveat; because of differing solubility of ions, the composition of the Earth's rocks, and consequences of the carbon cycle, the ocean isn't "balanced" - there's more calcium in the ocean than alkalinity as a molar ratio. What that means to an aquarist that's trying to maintain seawater chemistry is that alkalinity will fall much faster than calcium in a tank that's not dosed.

 

[Paul Bradford]

Emma, you should switch your salt mix to one that starts with the parameters you’re trying to maintain. Personally, I use the Tropic Marine Pro-Reef, but there are plenty others.