New DIY Two Part Recipes with Higher pH Boost

[Randy Holmes-Farley]

Dear Randy, I have been doing the calculations for the current recipe, just to see if I could replicate the current recipe. In these calculations the NSW-level is the target to "maintain" with the current recipe (not taking any trace elements into consideration. Natural Seawater Levels:
kH 7.0
Ca 412
Mg 1295
Sulfate 2701

I was unable to get to the same amount of magnesium when I targeted natural seawater levels. Only when I raised the amount of magnesium that needs to be replaced to 1613, I was able to exactly replicate the recipe.

As I was unable to replicate the recipe with the golden standard 20Ca per 2,8 kH, I wondered if this recipe indeed targets around 18,5 per 2,8 kH and why the amount of magnesium is higher than needed. (especially if the targeted Ca is around 20 per 2,8Kh.. the excess magnesium does not make any sense to me).

Jim discusses the detailed recipe (ignoring the hydroxide swap I made) here:

https://www.reef2reef.com/threads/s...hould-i-expect-to-change.215171/#post-2466696

And this is my rationale for the original mag amount:

After adding 594 grams of baking soda (1 gallon of Recipe #1), we will have added 163 grams of sodium. In natural seawater, magnesium is present at about 12.0% of the sodium concentration (by weight). In order to match the magnesium additions to the sodium additions to leave them in a natural ratio, we need to add 12% of 163 grams, or 19.5 grams, of magnesium for every gallon of the two-part additive that we add.

Additionally, we may want to account for magnesium that is actually incorporated into the coral skeletons. For this calculation, I have assumed that the amount of magnesium incorporated is about 6.5% of the calcium level (by weight), or about 2.5% of the skeleton by weight. In the course of adding this gallon of both parts of the two part supplement, we added 141 grams of calcium, so we need to add 0.065 x 141 = 9 grams of magnesium to account for this deposition.

 

[Randy Holmes-Farley]

The alk to calcium used is addressed here:

https://www.reef2reef.com/threads/s...y-alk-calcium-balanced-for-1-1-dosing.352634/

It is actually a bit tricky to know exactly how much calcium and alkalinity to have in a two part for two reasons (detailed below), but it is expected that the demand for calcium in a reef tank when using a two part is below the ratio needed for production of pure calcium carbonate due to replacement of some of the calcium demand by magnesium and strontium getting into the calcium carbonate crystal in place of calcium.

In my DIY two part (like from BRS), I chose to use slightly less calcium relative to alkalinity. My calcium part is intended to have 37,000 mg/L calcium (0.92 M) and the alk part has 1.9 eq/L alkalinity. Thus it is intended to have a slight excess of alkalinity relative to calcium. It may not be perfect, depending how the factors discussed below play out in any given reef tank, but it is in the right direction.

Note, the math discussion below is only for chemical/math nerds, and is really shown only so that folks do not throw out the criticism that I forgot these effects that impact the ratio of calcium to alkalinity needed in a reef tank:

1. Pure calcium carbonate does not form in reef aquaria. Magnesium and strontium get into the growing crystal of calcium carbonate, reducing the consumption of calcium relative to alkalinity. So even the "perfect" 1 mole of calcium for each 2 moles of alkalinity is a slight overestimate of the calcium required, and a perfect two part will require less calcium in relation to alkalinity by something like 12.5% (depending on exactly how much magnesium, especially, is getting incorporated, and that depends on exactly which organisms are present). I discuss that ratio in more detail here:

https://www.reef2reef.com/threads/r...g-three-parameters.321163/page-2#post-3981087

2. An even more esoteric effect relates to the salinity rise when using such a product from the sodium and chloride added. When the salinity is corrected back to normal, it reduces both calcium and alkalinity, requiring more dosing, but curiously, it doesn't require the same amount of each half to be dosed to offset this rise. I have calculated the salinity rise elsewhere,

http://reefkeeping.com/issues/2006-02/rhf/index.php

and it is on the order of a 32% rise in salinity after dosing 1.1 dKH per day for a year (both parts equally) for a total of 401.5 dKH (143.4 meq).

Let's take an example with a 100 liter tank, although tank size doesn't matter in this calculation. To add 401.5 dKH (143.4 meq/L) to 100 liters using the Seachem product with 4.4 eq/L (4,400 meq/L) takes 143.4 meq/L * 100 L /4,400 meq/L = 3.2 liters per year. At the end of that year, salinity has risen by about 32%.

Because of that salinity rise, when corrected back to normal, the alkalintiy decreases by 32%, so 9 dKH becomes 6.12 dKH, and requires extra additive to boost the alk back. That requires an extra 9-6.12 dKH = 2.88 dKH (1.03 meq/L) takes an additional 1.03 meq/l * 100 L / 4,400 meq/L = 0.023 L of alk additive. This effect is pretty small on top of the 3.2L added over that year, and corresponds to only an extra 0.7% of the additive.

The correction is not exactly the same for calcium. If we start at 420 ppm, a 32% drop brings calcium down to 286 ppm. To bring that back up by 420-286 = 134 ppm calcium takes 134 mg/L x 100 L / 100,000 mg/L = 0.13 L. That, in comparison to the ~3.2 L added over the year is a required correction of 4.1% of the total calcium added. So for calcium, this correction is not so trivially small, and tends to increase the amount of calcium needed.

 

[WWIII]

Just thought I'd chime back in here with my simpleton comments. I've been dosing this (2nd recipe) for nearly 2 months now. My ph is 8.16 to 8.4. I'm dosing 120 ml of each daily into a 250 gallon system. My corals are super happy and my small sps frags are really starting to take off! I maintain my alk between 8.3 and 8.5 dkh.

Here's a couple pics of a WD frag growth in those 2 months and a fts...

 

[Randy Holmes-Farley]

Just thought I'd chime back in here with my simpleton comments. I've been dosing this (2nd recipe) for nearly 2 months now. My ph is 8.16 to 8.4. I'm dosing 120 ml of each daily into a 250 gallon system. My corals are super happy and my small sps frags are really starting to take off! I maintain my alk between 8.3 and 8.5 dkh.

Great, thanks for the update!

 

[Tmmste]

The alk to calcium used is addressed here:

https://www.reef2reef.com/threads/s...y-alk-calcium-balanced-for-1-1-dosing.352634/

It is actually a bit tricky to know exactly how much calcium and alkalinity to have in a two part for two reasons (detailed below), but it is expected that the demand for calcium in a reef tank when using a two part is below the ratio needed for production of pure calcium carbonate due to replacement of some of the calcium demand by magnesium and strontium getting into the calcium carbonate crystal in place of calcium.

In my DIY two part (like from BRS), I chose to use slightly less calcium relative to alkalinity. My calcium part is intended to have 37,000 mg/L calcium (0.92 M) and the alk part has 1.9 eq/L alkalinity. Thus it is intended to have a slight excess of alkalinity relative to calcium. It may not be perfect, depending how the factors discussed below play out in any given reef tank, but it is in the right direction.

Note, the math discussion below is only for chemical/math nerds, and is really shown only so that folks do not throw out the criticism that I forgot these effects that impact the ratio of calcium to alkalinity needed in a reef tank:

1. Pure calcium carbonate does not form in reef aquaria. Magnesium and strontium get into the growing crystal of calcium carbonate, reducing the consumption of calcium relative to alkalinity. So even the "perfect" 1 mole of calcium for each 2 moles of alkalinity is a slight overestimate of the calcium required, and a perfect two part will require less calcium in relation to alkalinity by something like 12.5% (depending on exactly how much magnesium, especially, is getting incorporated, and that depends on exactly which organisms are present). I discuss that ratio in more detail here:

https://www.reef2reef.com/threads/r...g-three-parameters.321163/page-2#post-3981087

2. An even more esoteric effect relates to the salinity rise when using such a product from the sodium and chloride added. When the salinity is corrected back to normal, it reduces both calcium and alkalinity, requiring more dosing, but curiously, it doesn't require the same amount of each half to be dosed to offset this rise. I have calculated the salinity rise elsewhere,

http://reefkeeping.com/issues/2006-02/rhf/index.php

and it is on the order of a 32% rise in salinity after dosing 1.1 dKH per day for a year (both parts equally) for a total of 401.5 dKH (143.4 meq).

Let's take an example with a 100 liter tank, although tank size doesn't matter in this calculation. To add 401.5 dKH (143.4 meq/L) to 100 liters using the Seachem product with 4.4 eq/L (4,400 meq/L) takes 143.4 meq/L * 100 L /4,400 meq/L = 3.2 liters per year. At the end of that year, salinity has risen by about 32%.

Because of that salinity rise, when corrected back to normal, the alkalintiy decreases by 32%, so 9 dKH becomes 6.12 dKH, and requires extra additive to boost the alk back. That requires an extra 9-6.12 dKH = 2.88 dKH (1.03 meq/L) takes an additional 1.03 meq/l * 100 L / 4,400 meq/L = 0.023 L of alk additive. This effect is pretty small on top of the 3.2L added over that year, and corresponds to only an extra 0.7% of the additive.

The correction is not exactly the same for calcium. If we start at 420 ppm, a 32% drop brings calcium down to 286 ppm. To bring that back up by 420-286 = 134 ppm calcium takes 134 mg/L x 100 L / 100,000 mg/L = 0.13 L. That, in comparison to the ~3.2 L added over the year is a required correction of 4.1% of the total calcium added. So for calcium, this correction is not so trivially small, and tends to increase the amount of calcium needed.

Awsome! The ratio kH/Ca is automatically calculated (like in the other topic where I explained the 2-part based on jimmy54 theory... which he probably got from you ofcourse. In this topic you where looking for the 1:5 gram of Ca:Mg). I'll check the articles too see if I can use the same numbers or new information. I "think" the additional magnesium balances out the sodium:chloride ratio in this case, but increase magnesium levels higher than intended. Although I cannot afford making another mistake with this bold statement.. but I think.. according to my calculations.. Mg will rise higher than intended. However, I will triple check if I overlooked something. If the calculations are 100% correct though, it does allow to tweak the recipe easily to incorporate trace elements (Sr/K/I/B) and change the ratio for tanks which notice Ca and kH become a bit more skewed (Ca rises or falls relative to kH). I'll get back to this as soon as I checked everything, I'll note down the calculations to back it up. I think DIY recipes are the future.. every method has their own composition.. but in the end it all boils down to this. I love it.

 

[Randy Holmes-Farley]

Awsome! The ratio kH/Ca is automatically calculated (like in the other topic where I explained the 2-part based on jimmy54 theory... which he probably got from you ofcourse. In this topic you where looking for the 1:5 gram of Ca:Mg). I'll check the articles too see if I can use the same numbers or new information. I "think" the additional magnesium balances out the sodium:chloride ratio in this case, but increase magnesium levels higher than intended. Although I cannot afford making another mistake with this bold statement.. but I think.. according to my calculations.. Mg will rise higher than intended. However, I will triple check if I overlooked something. If the calculations are 100% correct though, it does allow to tweak the recipe easily to incorporate trace elements (Sr/K/I/B) and change the ratio for tanks which notice Ca and kH become a bit more skewed (Ca rises or falls relative to kH). I'll get back to this as soon as I checked everything, I'll note down the calculations to back it up. I think DIY recipes are the future.. every method has their own composition.. but in the end it all boils down to this. I love it.

FWIW, the magnesium consumption can only be an estimate, since it depends on which organisms consume the calcium and alk.

Aquarium Chemistry: Magnesium In Reef Aquaria ? Advanced Aquarist | Aquarist Magazine and Blog
https://web.archive.org/web/20060215114038/https://www.advancedaquarist.com/issues/oct2003/chem.htm

See Table 1.

Coral skeletons range from 0.05% to 4.4% magnesium by weight, the remainder being primarily calcium carbonate.

 

[Tmmste]

FWIW, the magnesium consumption can only be an estimate, since it depends on which organisms consume the calcium and alk.

Aquarium Chemistry: Magnesium In Reef Aquaria ? Advanced Aquarist | Aquarist Magazine and Blog
https://web.archive.org/web/20060215114038/https://www.advancedaquarist.com/issues/oct2003/chem.htm

See Table 1.

Coral skeletons range from 0.05% to 4.4% magnesium by weight, the remainder being primarily calcium carbonate.

I see yes, my calculation of the amount of magnesium much therefore be incorrect as I use the same calculations... so I started digging. I traced back the amount of magnesium needed; 75,7 gr sodiumhydroxide would equal 1,89 mole. 94,7 gr calcium chloride anhydrate would equal equal 36000 ppm / 1,89 = 19 Ca per 2,8 kH. 19 Ca consumers 2,7 kH, leaving 0,2 for Mg 0,2 / 2,8 * 12,1525 = 0,87 gr mg / 0,11955 = 7,26 gr magnesium chloride hexahydrate.. (bit less than the 7,8 calculated that is would seem logical as there is more Ca per kH used) but..how much Mg is left.. 69 Mg in the recipe.. (1295 x 4,53 / 0,119661 ) - 49 gr magensium = 20 gr left.. a difference of 13 which must be incorrect on my part then. 7,26 x 1,89 mole would be already much closer with 13,74... leaving 6,25 gr per liter for "other processes". This difference could be filled when aiming to replenish a higher magnesium level. (although this would raise the amount of water to remove and so on.. ) but it is probably the 1,89 I did not multiply to the Mg calculations with that skewed the results. I'll continue reading your articles too see if I can find more details to improve on, thank you for all your efforts Randy!

 

[Tmmste]

Dear Randy, I have been "molding" the recipe to fit my own targets for kH/Ca/Mg/K/Sr/B and desired strength of the recipe. I wonder though if you have any suggestions regarding trace elements which may still be interesting to add. Perhaps manganese/molybdenum or something else? I hope you have some suggestions too add. Thank you in advance, Tim.

 

[Randy Holmes-Farley]

Despite 1% daily water changes, my tank potentially ran low in molybdenum, vanadium, and manganese, and I dosed iron. Those might be places to start.

Others I can't really know if the water changes were enough since ICP cannot test low enough to really say about (e.g., cobalt, chromium)

 

[Tmmste]

Despite 1% daily water changes, my tank potentially ran low in molybdenum, vanadium, and manganese, and I dosed iron. Those might be places to start.

Others I can't really know if the water changes were enough since ICP cannot test low enough to really say about (e.g., cobalt, chromium)

I see, which form of e.g. molybdenum and manganese would you recommend? I would like to add most chemicals to the Ca or kH mix.. I believe none of those two can be added to the kH mix though.. and if I can add the dry powders or would I need a chelated form like with iron? (I have no clue which elements react with each other or if trace elements need to be dissolved in a certain order). I will be feeding a lot and assume there must be some trace elements in foods too.

 

[Randy Holmes-Farley]

Here's molybdenum and manganese:
https://www.reef2reef.com/threads/post-your-diy-additives-here.344149/#post-4419386

 

[Tmmste]

Here's molybdenum and manganese:
https://www.reef2reef.com/threads/post-your-diy-additives-here.344149/#post-4419386

Thank you for pointing to this topic, I posted a reply there as I think it is more a trace-element specific question. Hopefully you can leave a reply there too haha. Thanks Randy!

 

[laverda]

Sulfate is the third most abundant ion in seawater by weight. If you do not have sufficient amounts of it in a two part, chloride will rise and sulfate will fall. It's not entirely clear what the effect might be of that.

How can you tell if your Sulfate and Chloride are balanced properly or not? Is there a test kit?
Learning a lot in this thread. Thanks Randy and everyone that has posted.

 

[Tmmste]

How can you tell if your Sulfate and Chloride are balanced properly or not? Is there a test kit?
Learning a lot in this thread. Thanks Randy and everyone that has posted.

By calculating how much Na & CI you are adding to your tank including the amounts added additionally to correct the salinity rise and compensation for the lost elemenrs (delending on your targets). In your compensation for the lost elements there will be a certain amount of water that will be removed from your tank (via skimmer.. manual removal). If that is e.g. 2 liter per liter stock . than per liter 2.7 grams of sulfate is lost.. (and per liter around 30,15 gr of tablesalt NaCI.. depends on the Na and CI ratio and amount in the bucket of salt..) calfulate how much sodium sulfate contains that amount of sulfate, don't forget to add the sodium and then you will have your total amounts of Na:CI:So4. Is Na is around 55% of CI and SO4 13,8% of CI then you are a bit closer to natural seawater...

 

[Randy Holmes-Farley]

How can you tell if your Sulfate and Chloride are balanced properly or not? Is there a test kit?
Learning a lot in this thread. Thanks Randy and everyone that has posted.

A test by icp is the way folks can tell. There aren’t test kits for it.[emoji3]

 

[laverda]

By calculating how much Na & CI you are adding to your tank including the amounts added additionally to correct the salinity rise and compensation for the lost elemenrs (delending on your targets). In your compensation for the lost elements there will be a certain amount of water that will be removed from your tank (via skimmer.. manual removal). If that is e.g. 2 liter per liter stock . than per liter 2.7 grams of sulfate is lost.. (and per liter around 30,15 gr of tablesalt NaCI.. depends on the Na and CI ratio and amount in the bucket of salt..) calfulate how much sodium sulfate contains that amount of sulfate, don't forget to add the sodium and then you will have your total amounts of Na:CI:So4. Is Na is around 55% of CI and SO4 13,8% of CI then you are a bit closer to natural seawater...

Thank you for your detailed explanation. Sadly it is way over my head at this point.

 

[laverda]

A test by icp is the way folks can tell. There aren’t test kits for it.[emoji3]

Thank you.

 

[Tmmste]

Thank you for your detailed explanation. Sadly it is way over my head at this point.

That is ok, I am not a chemist at all. However, if you feel comfortable with excell you can figure it out. Well.. I kept on stalking Randy and people on a Dutch forum untill I figured it out. But it is very satisfying if you know "how" stuff is calculated, you then really you will DIY everything because it is so incredibly cheap.. and you will also realize you need to follow a "method" not because they are different.. but because companies make a massive amount of profit on it. E.g. I can make a kH+ for € 0.07. and Red Sea sells it as "formula a or b" for € 33 euros. Trace elements are even more rediculous.. sometimes being 2000x more expensive than if you would calculate what it costs to make it yourself. (think about it.. it is a trace element.. so 99,9% in the bottle is water)

 

[laverda]

FWIW, I wouldn’t agonize over the chloride to sulfate ratio. It seems to vary substantially between salt mixes and between tanks that are seemingly thriving. [emoji3]

Glad to read that, as I was concerned. I am slowly reading, rereading, taking notes & learning more from this thread.

 

[Long Tran]

Hi all, since I am going to implement to the Sodium Hydroxide version to boost PH, please help me to confirm the list items below before I order. Since the primary purpose of the revised true 2-part dosing is to saving cost and improved the effect, i am trying not only to gather all items at lowest cost, but also achieve the best result.

Calcium Chloride Dihydrate:
https://www.homedepot.com/p/Snow-Jo...-Pellets-Ice-Melter-Jug-MELT10CCP-J/206403605 .

https://www.homedepot.com/p/Preston...}:st++cn:{0:0}++prestone+{brand}+heat+{rest}+

Is the Snow Joe Melk here Calcium Chloride Dihydrate or the Prestion Driveway Heat OK to use?

Magnesium Chloride:
I think BRS has good price. Do you guys have other places to shop for cheaper?
https://www.bulkreefsupply.com/brs-bulk-magnesium-chloride-aquarium-supplement.html


Sodium Hyroxide and Sodium Sulfate:
Is amazon only place we can shop for this? any other places?

https://www.amazon.com/Sodium-Hydro...0858376&sr=8-5&keywords=sodium+hydroxide&th=1

https://www.amazon.com/Natural-Sulfate-Granular-Anhydrous-Crystals/dp/B00L4L73CM

Thanks.