# Latest insights on Calcium



## Yugang (6 Feb 2022)

On this and other fora I am reading sometimes contradictory statements regarding Ca and Ca deficiency, ranging from "Ca deficiency is extremely rare" to "Ca ppm should be a multiple of Mg ppm and in the range of 20-30 ppm".

I observe that some have the experience that 3-5 ppm of Ca is sufficient, others believe we need gH boosters and bring Ca to non-limiting 30 ppm. In GH boosters Ca is usually included in significant amounts, is that because we know that is needed?

As usual in the hobby, after some debate the conclusion may be "it depends". I am now trying to understand "depends on what", as most likely we are again all right from our own perspective 

My personal experience: I have seen definitely how Mg impacts my plants, but not sure about Ca. My Ca ppm < Mg ppm. Not sure if adding CaCl will be any beneficial, and when.


----------



## Happi (6 Feb 2022)

just to give you an idea look at the graph below. like I said plant don't need that much Ca, I think people still add higher calcium because that is what they been told to add for very long time now or they add it because they believe that plant, shrimps, fishes etc. needs that much. but higher calcium will protect the plant from several different toxicity to the plants, boron is one good example.

Marschner's Mineral:


----------



## Yugang (6 Feb 2022)

I am quickly out of my depth on this one, and wait for others to chime in.

Just an ignorant thought - does it make sense to think that plant uptake, % of plant mass, and preferred ppm the plant is swimming in are three entirely different measures and only partially correlated?

I believe for clarity we should talk about preferred Ca ppm in the water column (ignoring substrate for a moment), does that make sense?


----------



## Happi (6 Feb 2022)

Yugang said:


> I am quicly out of my depth on this one, and wait for others to chime in.
> 
> Just an ignorant thought - does it make sense to think that plant uptake, % of plant mass, and preferred ppm the plant is swimming in are three entirely different measures and only partially correlated?
> 
> I believe for clarity we should talk about preferred Ca ppm in the water column (ignoring substrate for a moment), does that make sense?


Yes it make sense. So you want to know the preferred calcium in the water? 
But preferred by who? Plants, fish, shrimps?


----------



## Yugang (6 Feb 2022)

Happi said:


> Yes it make sense. So you want to know the preferred calcium in the water?
> But preferred by who? Plants, fish, shrimps?


Perhaps we first discuss plants, as that may be confusing enough in itself?
If somebody raises a red flag and says  fish and shrimp are at risk at low Ca in water column, I will bump it up immediately.


----------



## Yugang (6 Feb 2022)

Borrowing Darrel's posting from the other thread on GH booster:



dw1305 said:


> Hi all,
> 
> I don't think it serves any useful purpose in terms of plant growth for most plants (there maybe exceptions in "hard water" plants) but it does allow the vendor of the "GH booster" to sell more product, and calcium chloride (CaCl2.2H2O) is a pretty cheap chemical to buy.
> 
> cheers Darrel



(note: food grade CaCl may be cheap to buy, yet less cheap to ship to hk in sufficient quantity   I would personally be happy if I learn from this thread that 5 ppm Ca is enough for most plants)

Would we say that we could have a low Ca ppm in water column (3-5 ppm?), even when Mg is dosed at higher ppm to avoid chlorosis? Is the often seen statement that we need a  ( Ca/Mg ratio = 2 or 3 ) then no longer considered valid?

Are there still any views that support the 20-30 ppm Ca target as per the Nutrient dosing calculator, or is there consensus this is merely driven by 'commercial arguments'?


----------



## plantnoobdude (6 Feb 2022)

Yugang said:


> this is merely driven by 'commercial arguments'?


no it's driven by EI philosphy. another example is K dosage. because plants always use N more than K. which means in theory, no3:k ratio of 4:1 should be more than sufficient. yet, EI users regularly add same or more amount of K compared to No3.


----------



## Yugang (6 Feb 2022)

plantnoobdude said:


> no it's driven by EI philosphy. another example is K dosage. because plants always use N more than K. which means in theory, no3:k ratio of 4:1 should be more than sufficient. yet, EI users regularly add same or more amount of K compared to No3.


May I play devils advocate (I am not very knowledgeable on plants)?
Mg is nearly always earmarked as an essential nutrient, while for Ca most dosing schemes do not even set a target. Why would we dose Ca 2-3 times more than Mg?


----------



## plantnoobdude (6 Feb 2022)

mostly based on terrestrial plant data. but above, is critical concentration of nutrients in Elodea nuttalli, you can see the ratio is close to 3:1. my tank is dosed to 18ppm Ca and 6ppm Mg ~4dgh. a good middle ground between keeping water collumn dosing minimal and shrimp happy i think. @Yugang


----------



## Yugang (6 Feb 2022)

plantnoobdude said:


> View attachment 181778
> mostly based on terrestrial plant data. but above, is critical concentration of nutrients in Elodea nuttalli, you can see the ratio is close to 3:1. my tank is dosed to 18ppm Ca and 6ppm Mg ~4dgh. a good middle ground between keeping water collumn dosing minimal and shrimp happy i think. @Yugang


Could you help me read this table, Ca 2800 mg/kg? Are we referring to plant tissue or water column? How do we get to the often quoted 30 ppm Ca in the water column, if this table is to clarify that?


----------



## erwin123 (6 Feb 2022)

I'm surprised that you can't buy food grade CaCl2 from a DIY bakery/chef/cooking store.  It costs like $2.20 for a 250g tub in my country. 








						RedManShop | CALCIUM CHLORIDE 250G
					

RedManShop is the leader Baking Supplies online store. Free Delivery Above $88




					www.redmanshop.com


----------



## Yugang (6 Feb 2022)

erwin123 said:


> I'm surprised that you can't buy food grade CaCl2 from a DIY bakery/chef/cooking store.  It costs like $2.20 for a 250g tub in my country.
> 
> 
> 
> ...


98 HKD, 9.5 GBP per 1 Oz. bottle in baking shop.









						Calcium Chloride Liquid 氯化鈣
					

Description Ingredients More info Calcium chloride is an additive used in cheesemaking used with store-bought milk and goats milk to create a firmer setting curd for easier cutting when making of hard cheeses.  The heat-treating process most commercial milk goes through decreases the amount of...




					www.bakingwarehouse.com


----------



## plantnoobdude (6 Feb 2022)

Yugang said:


> Could you help me read this table, Ca 2800 mg/kg? Are we referring to plant tissue or water column? How do we get to the often quoted 30 ppm Ca in the water column, if this table is to clarify that?


it's mg per kg of plant tissue i believe.
the table was meant to clarify why we use such ratios in planted aquariums.
also see marschner ratio, a set of numbers for trrestrial plants.
N 1
K 0.6666
Ca 0.3332
Mg 0.1332
P 0.1332
S 0.066666
Cl 0.006666
Fe 0.006666
B 0.001332
Mn 0.003332
Zn 0.001332
Cu 0.0004
Mo 0.0000066
Ni 0.0000066
and the critical concentration ratio for elodea is quite close as well.
N 1
P 0.0875
K 0.5
Ca 0.175
Mg 0.0625

Fe 0.00375
Mn 0.00025
B 0.00008125
Zn 0.0005
Cu 0.00005
Mo 0.000009375
S 0.05

Ca to Mg in both cases quite close to 3:1.
I think it's just most tapwater has values close to 30:10 and its fairly convenient to work with, shrimp and plants included. you could go much lwoer as happi says if you only have fish and plants.


----------



## Yugang (6 Feb 2022)

plantnoobdude said:


> it's mg per kg of plant tissue i believe.


but isn't 2800 mg/kg something like 2800 ppm, and then in plant tissue? Isn't it a bit of a stretch to translate that to a 30 ppm water column dosing. Where do I go wrong?



plantnoobdude said:


> trrestrial plants.


Correct, you know what I'm going to say  

If it is only the ratio that the table clarifies, how credible is it after all the caveats? And how do we get to 30 ppm for Ca? 
Sorry again for playing devils advocate, just try to understand where I miss the point  

I have a feeling that the outcome will be that 5 ppm Ca dosing is sufficient, but am cautious concluding that with EI assumptions we got it so wrong  -- hence trying to clarify the latter.


----------



## Maf 2500 (6 Feb 2022)

Yugang said:


> but isn't 2800 mg/kg something like 2800 ppm, and then in plant tissue? Isn't it a bit of a stretch to translate that to a 30 ppm water column dosing. Where do I go wrong?


For the results of that test they would have dehydrated the plant tissue completely before analysing it, hence the high ppm. The ratios remain relevant of course. (If you dehydrate your 30ppm water column it would also increase.)

As has been mentioned by others shrimp need a higher ppm of calcium than aquatic plants do. EI supplies nutrients far in excess of those actually needed, thus the higher ppm of Ca than plants actually require.


----------



## erwin123 (6 Feb 2022)

Would too much calcium in the water column affect EDTA-Fe? Read on the internet about "Calcium replacing Fe in the chelate" or something like that.


----------



## plantnoobdude (6 Feb 2022)

erwin123 said:


> Would too much calcium in the water column affect EDTA-Fe? Read on the internet about "Calcium replacing Fe in the chelate" or something like that.


never heard of that, but Ca and Fe seem to have antagonistic relationship.
lets refer to mulders chart.


----------



## dw1305 (6 Feb 2022)

Hi all, 


erwin123 said:


> Read on the internet about "Calcium replacing Fe in the chelate" or something like that.


No, iron (Fe) is one of the most <"strongly bound cations">, it only becomes available due to photodegradation of the chelate. It actually works the other way around, with <"iron replacing less strongly bound cations">.

I think the think the thing to remember when talking about calcium (Ca++) (and bicarbonate (2HCO3-)  is that a very considerable proportion of the World's freshwater (and all the World's seawater) is fully saturated with Ca++ and HCO3- ions, due to <"the solubility limit of CaCO3"> and the <"large amount of limestone"> present in Global terms.

If you look at that as  dGH and dKH? The maximum solubility of CaCO3 (at 415 ppm CO2) works out at <"about  18 dGH and 18 dKH">.  If you work from one dGH  &  one dKH = 17.86 mg / L (ppm) of CaCO3 <"that is ~125 mg / L Ca">.  This is why some plants can use bicarbonate (HCO3-) <"as their carbon source">, and are very efficient at <"sequestering  iron (Fe++(+)) ions"> etc., they don't have any alternative. 

In N. Europe most of the limestone aquifers are <"Cretaceous age Chalk and Jurassic age limestones"> and they are both pretty pure CaCO3. It is <"different in S. Europe"> and <"N. America"> where some of the limestones have undergone "dolomitization" and contain MgCO3 as well. 

cheers Darrel


----------



## erwin123 (6 Feb 2022)

Soil Basics, Management and Rhizosphere Engineering for Sustainable Agriculture
					

Increase in global population, drastic changes in the environment, soil degradation and decrease in quality and quantity of agricultural productivity warranted us to adapt sustainable farming practices. This book focuses on soil health management and creating biased rhizosphere that can...



					books.google.com.sg
				



Thanks. I am really benefiting from these chemistry lessons. Anyway, this is the passage which I may have misread, sorry didn't post it earlier.


----------



## Happi (6 Feb 2022)

@Yugang

I use to grow plant in odd ratio of Ca:Mg at 1:4 and they did quite well, but this ratio is not a problem, but the problem would be if this ratio was to be used at 30 ppm Ca and 120 ppm Mg, because the concentration is very high. 
adding 30 ppm Ca seems to cover wide range of area for those who like to keep fish, shrimps and plants at the same time, for the plant alone, this 30 ppm of calcium is never needed.  if your water contain 30 ppm Ca, plant might only use 1 ppm Ca and rest of the 29 ppm Ca will remain in your water. 

most people only add Mg to their changed water, because there is plenty of Ca in their water to begin with, weather you have 30, 50, 100 ppm Ca and adding even 1,3, 5 ppm Mg in this case will always be beneficial. 

I have some idea which could  be highly beneficial for those who have a hard water, if they were to add Diethylenetriamene pentaacetate to their aquarium water, this will chelate several nutrients that are already present in their tap water.


----------



## dw1305 (6 Feb 2022)

Hi all, 






erwin123 said:


> I am really benefiting from these chemistry lessons.


I didn't know why FeEDTA is ineffective at higher pH levels, so it is useful to know why and the reason for it,

cheers Darrel


----------



## X3NiTH (6 Feb 2022)

This is the Affinity chart for EDTA.





EDTA is environmentally persistent (only seen to be dismantled by a species of bacteria that grows in the pond waters of nuclear power stations), when it looses its bond to the metal ion it is chelated with either via plant uptake, pH effect or photolysis then the next ion to be chelated will be dependant on presence and pH. If the pH is low then it can re-uptake heavier metal ions, if the pH is above neutral and out of range for FeEDTA then it will preferentially bind with Calcium when the Iron is dropped.


----------



## arcturus (6 Feb 2022)

plantnoobdude said:


> no it's driven by EI philosphy. another example is K dosage. because plants always use N more than K. which means in theory, no3:k ratio of 4:1 should be more than sufficient. yet, EI users regularly add same or more amount of K compared to No3.


But isn't this a consequence of the salts commonly used with EI, especially because this regime is often used with RO water? The common fertilization and remineralization salts tend to favour K. It is possible to avoid high values of K, but this would lead to higher amount of Ca and/or Mg. These common salts will always introduce an amount of K, Ca, or Mg significantly above what is considered sufficient.


----------



## arcturus (6 Feb 2022)

plantnoobdude said:


> View attachment 181778
> mostly based on terrestrial plant data. but above, is critical concentration of nutrients in Elodea nuttalli, you can see the ratio is close to 3:1. my tank is dosed to 18ppm Ca and 6ppm Mg ~4dgh. a good middle ground between keeping water collumn dosing minimal and shrimp happy i think. @Yugang


But this table only shows that the plant is _storing _Ca and Mg at a 3:1 ratio. It says nothing about the availability of these nutrients outside the plant. Especially, it does not say that a 1:1 or any other ratio in the environment is detrimental to plant or favours the plant.


----------



## MichaelJ (6 Feb 2022)

dw1305 said:


> Hi all,
> 
> 
> 
> ...



Quote: "Above the pH of 6.5 nearly 50% of the iron is unavailable". ...   thats the one that is puzzling to me...  What exactly does it mean?  is it "instantly" unavailable ? what roles does time play here?  How fast does plants mop up the Fe vs. the timeframe when the Fe becomes unavailable etc. ?   Is it _really_ something we have to worry about?

In the past I have run both my densely planted tanks very successfully in the 7.2-7.6 pH ange dosing ~1.0 ppm EDTA Fe and never suffered from Iron deficiencies.  (I'm currently closer to ~6.5 after starting with botanicals @ low KH).

Regards,
Michael


----------



## plantnoobdude (6 Feb 2022)

arcturus said:


> But isn't this a consequence of the salts commonly used with EI, especially because this regime is often used with RO water? The common fertilization and remineralization salts tend to favour K. It is possible to avoid high values of K, but this would lead to higher amount of Ca and/or Mg. These common salts will always introduce an amount of K, Ca, or Mg significantly above what is considered sufficient.


I mean, Cano3. 20ppm no3 will get ~6ppm Ca, from there add some kh2po4 and top up k with some k2so4.


----------



## arcturus (6 Feb 2022)

plantnoobdude said:


> I mean, Cano3. 20ppm no3 will get ~6ppm Ca, from there add some kh2po4 and top up k with some k2so4.


But with RO water this would lead to an dGH ~0.9° (and zero dKH). Same if using MgNO3. If you want to target a dGH of ~6° then you need to start adding Mg and Ca, leading to Ca and Mg (and Cl or SO4) values way above the "sufficient".


----------



## plantnoobdude (6 Feb 2022)

arcturus said:


> But this table only shows that the plant is _storing _Ca and Mg at a 3:1 ratio. It says nothing about the availability of these nutrients outside the plant. Especially, it does not say that a 1:1 or any other ratio in the environment is detrimental to plant or favours the plant.



 the amount being stored is different to critical concentration. the amount that the plant is storing Ca and Mg is at a very different ratio
around 3:2. elements found inside plants are not particularly useful, especially because of luxury uptake.



critical concentration is  the collumn on the left, which aligns very closely to 3:1 ratio. critical concentration is defined as
"Critical level or concentration is a term that is common in both soil and plant analysis. It is usually defined in plant analysis as the level that results in 90% of maximum yield or growth"





						Plant Analysis - Nutrient Management
					

Plant analysis refers to the measurement of essential nutrient content of plant tissue by laboratory analysis. There have been many advances in plant analysis.




					www.cropnutrition.com
				




such ratios are not particularly useful untill you get into toxicity ranges or other issues, but if you are trying to add as little as possible and keep the water collumn lean then it is advisable to use such a ratio.

*"Especially, it does not say that a 1:1 or any other ratio in the environment is detrimental to plant or favours the plant."*

 i was just explaining why the 3:1 ratio is commonly used. im not saying 3:1  ratio is perfect for every tank and plant, just why people choose to use it quite a lot.

i answered this question by Yugang.
"Mg is nearly always earmarked as an essential nutrient, while for Ca most dosing schemes do not even set a target. Why would we dose Ca 2-3 times more than Mg?"
 I said it's mostly because of terrestrial plant data.


----------



## arcturus (6 Feb 2022)

plantnoobdude said:


> the amount being stored is different to critical concentration. the amount that the plant is storing Ca and Mg is at a very different ratio
> around 3:2. elements found inside plants are not particularly useful, especially because of luxury uptake.
> 
> critical concentration is  the collumn on the left, which aligns very closely to 3:1 ratio. critical concentration is defined as
> "Critical level or concentration is a term that is common in both soil and plant analysis. It is usually defined in plant analysis as the level that results in 90% of maximum yield or growth"



My point is that it is the concentration of the nutrient in the plant tissue, not in the environment. Is there a correlation between the concentration of nutrient in the environment and that in the plant tissue? If we have a 1:1 ratio in the environment the plant may end up storing those two elements in whatever ratio (assuming we are not in the deficiency range).


----------



## plantnoobdude (6 Feb 2022)

arcturus said:


> My point is that it is the concentration of the nutrient in the plant tissue, not in the environment.


well, the numbers above are the minimum amount of nutrients plants must have to grow unrestricted. if the numbers go above the numbers the plant will store the excess inside plant tissue due to luxury uptake. i do not know the exact relationship but i assume if the amount of nutrients in the environment above critical concentration is 1:1 the plant will store it in plant tissue as one to one.



arcturus said:


> But with RO water this would lead to an dGH ~0.9° (and zero dKH). Same if using MgNO3. If you want to target a dGH of ~6° then you need to start adding Mg and Ca, leading to Ca and Mg (and Cl or SO4) values way above the "sufficient".


that is the entire point right? keeping nutrients low, seeing if lower amounts are sufficient. dgh of 6 is way above what is needed, that is the point of EI. unless you use inert sub and full rodi water with no so4 and cl then it is very unlikely to see cl, so4 deficiency.


----------



## X3NiTH (6 Feb 2022)

MichaelJ said:


> "Above the pH of 6.5 nearly 50% of the iron is unavailable". ... thats the one that is puzzling to me... What exactly does it mean? is it "instantly" unavailable ? what roles does time play here?



This is the Graph you are looking for.


----------



## X3NiTH (6 Feb 2022)

I should point out that that’s not the whole picture because it doesn’t take into account de-chelation through irradiance which will occur any time the tank lights are on, here’s a comparison of FeEDTA and FDTPA under irradiance.


----------



## Yugang (6 Feb 2022)

plantnoobdude said:


> that is the entire point right? keeping nutrients low, seeing if lower amounts are sufficient. dgh of 6 is way above what is needed, that is the point of EI



with regard to *Ca deficiency in plants*, are we in agreement that:

*3-5 ppm Calcium in the water column  is generally sufficient, or even preferred, for aquarium plants.*
       - Some exceptions for hard water plants.        
        - Irrespective of lighting, CO2, Mg and other nutrient dosing method.
        - *This is not taking into account the requirements of invertebrates and fish*.


----------



## X3NiTH (6 Feb 2022)

I would suggest that the minimum amount of Ca needed would correlate with the maximum amount available in rain, it’s a tough life but some plants have to live it!


----------



## Happi (6 Feb 2022)

@MichaelJ​look into "Haifa Cal Prime 17-0-0 calcium nitrate" if you want better version of Cano3. Haifa Cal Prime 17-0-0 calcium nitrate fertilizer 55 lb. -AO


----------



## MichaelJ (7 Feb 2022)

X3NiTH said:


> This is the Graph you are looking for.
> 
> View attachment 181839


Hi @X3NiTH  Brilliant! Now, that curve seems like a dead giveaway that the choice of EDTA is not _really_ an issue even at relatively high pH provided that you compensate by overshooting a bit on the weekly dosing (which we are all probably doing already...).



X3NiTH said:


> I should point out that that’s not the whole picture because it doesn’t take into account de-chelation through irradiance which will occur any time the tank lights are on, here’s a comparison of FeEDTA and FDTPA under irradiance.
> 
> View attachment 181843


I am not quite sure how to interpret these two curves? 

Cheers,
Michael


----------



## MichaelJ (7 Feb 2022)

Happi said:


> @MichaelJ​look into "Haifa Cal Prime 17-0-0 calcium nitrate" if you want better version of Cano3. Haifa Cal Prime 17-0-0 calcium nitrate fertilizer 55 lb. -AO


Thanks @Happi I'll look into it!

Cheers,
Michael


----------



## Happi (7 Feb 2022)

MichaelJ said:


> Thanks @Happi I'll look into it!
> 
> Cheers,
> Michael


the calculation would be different from any other Cano3, but here it is just in case:

500 ml, 20 ml per 50 gallon
20.135 gram Haifia Cal Prime

Ca    1
Total N    0.723
N-NO3    0.71
N-NH4    0.01276

*almost 7.9 gram less compared to other CaNO3 *


----------



## MichaelJ (7 Feb 2022)

Yugang said:


> Why would we dose Ca 2-3 times more than Mg?


That is a very good question @Yugang.  When you look at natural habitats it doesn't seem like Mother Nature is being excessively caught up in ratios....  for instance Chemistry of different amazonian water types. shows waterways with anything from 1:1 to 8:1 with regards to Ca:Mg contents. (but there seems to be a trend there around ~4:1) ... as a matter of fact it seems like Mother Nature is following a pretty hardcore homeopathic dosing regime 

Cheers,
Michael


----------



## Happi (7 Feb 2022)

Mother nature:


----------



## Yugang (7 Feb 2022)

MichaelJ said:


> That is a very good question @Yugang.  When you look at natural habitats it doesn't seem like Mother Nature is being excessively caught up in ratios....  for instance Chemistry of different amazonian water types. shows waterway with anything from 1:1 to 8:1 with regards to Ca:Mg contents. (but there seems to be a trend there around ~4:1) ... as a matter of fact it seem like Mother Nature is following a pretty hardcore homeopathic dosing regime
> 
> Cheers,
> Michael


Agree, and it is well understood that several aquarium dosing regimes are not trying at all to replicate nature.

My concern is that we are missing something, as there are many references over the past decade on several fora that say that Ca should in fact not be too low. Is this all a myth, or driven by unscientific arguments? Are we in fact boosting GH for our shrimp, and can we forget about it for plants? I remember reading T Barr somewhere (if my memory serves me right) who advices KH 2,3 and GH some points higher. Are these views from very educated plantkeepers now considered outdated?

EDIT: T Barr March 17, 2006 Barreport on optimal GH and KH.
"More likely I said a GH of 5 and KH of 3. GH should always be higher than KH if you have a choice."


----------



## MichaelJ (7 Feb 2022)

Yugang said:


> Agree, and it is well understood that several aquarium dosing regimes are not trying at all to replicate nature.





Yugang said:


> My concern is that we are missing something, as there are many references over the past decade on several fora that say that Ca should in fact not be too low. Is this all a myth, or driven by unscientific arguments?


Considering  plants only, there is definitely heaps of evidence that suggest that you can go fairly low on your Ca levels even in a densely planted  high energy tank, but Ca is still considered a Macro nutrient along with N, P, K, S and Mg.

Cheers,
Michael


----------



## Happi (7 Feb 2022)

Hoagland Solution is quite popular for hydroponic, which might be the closest thing to our aquarium plants. 

N     5      (22.1 ppm NO3)
K     5.6
Ca    4.762
P     0.738    (2.26 ppm PO4)
S     1.523
Mg     1.142
B     0.012
Fe     0.023 - 0.12
Mn     0.012
Zn     0.0012
Cu     0.000476
Mo     0.000238


----------



## Yugang (7 Feb 2022)

Yugang said:


> with regard to *Ca deficiency in plants*, are we in agreement that:
> 
> *3-5 ppm Calcium in the water column is generally sufficient, or even preferred, for aquarium plants.*
> 
> ...


Perhaps I go with this, unless someone corrects us and has some good argument that 20-30 ppm Ca really makes sense.

Still need to understand why my shrimp are doing so well, they breed like .... ehhhmmm ... shrimp 
I may still up my Ca for their wellbeing, when they are not shrimping


----------



## Happi (7 Feb 2022)

Yugang said:


> Perhaps I go with this, unless someone corrects us and has some good argument that 20-30 ppm Ca really makes sense.
> 
> Still need to understand why my shrimp are doing so well, they breed like .... ehhhmmm ... shrimp
> I may still up my Ca for their wellbeing, when they are not shrimping


we have Plant/Fish data to support some claims, but I couldn't find any relevant data on Shrimps to support the Calcium claims. if anyone found anything related to the shrimps and the water parameter they live in then we can go from there.

*Neocaridina davidi "these shrimp have also been discovered in the thermally polluted Erft and its tributary Gillbach Rivers in Germany"*

maybe that's why people like to raise the TDS  haha


----------



## Happi (7 Feb 2022)

this is all i could find so far: https://smujo.id/biodiv/article/download/4975/3908/22411


----------



## MichaelJ (7 Feb 2022)

Yugang said:


> Perhaps I go with this, unless someone corrects us and has some good argument that 20-30 ppm Ca really makes sense.


This is an older reference, but may be helpful; some measurements from river tributaries with Bee/Cheery shrimps. Notice the almost universal high Ca and Mg contents.

Cheers,
Michael


----------



## erwin123 (7 Feb 2022)

Yugang said:


> Perhaps I go with this, unless someone corrects us and has some good argument that 20-30 ppm Ca really makes sense.
> 
> Still need to understand why my shrimp are doing so well, they breed like .... ehhhmmm ... shrimp
> I may still up my Ca for their wellbeing, when they are not shrimping



maybe the food you feed them also contains calcium and magnesium? I think most shrimp food has Ca and Mg?


----------



## Yugang (7 Feb 2022)

erwin123 said:


> maybe the food you feed them also contains calcium and magnesium? I think most shrimp food has Ca and Mg?


Correct, I checked the packaging and mentions explicitly extra Calcium.
I also add one grinded eggshell weekly to my tank, I am reading that works as well, just as cuttlebone etc.

For the wellbeing of shrimp and snails, I will gradually increase my Ca dosing for them in the form of CaCl.

P.S. what I find confusing is that advice on shrimp usually indicates optimum GH. As Ca, Mg and other elements are not interchangeable for the health of a shrimp, this seems not very logical.


----------



## Hufsa (7 Feb 2022)

Yugang said:


> P.S. what I find confusing is that advice on shrimp usually indicates optimum GH. As Ca, Mg and other elements are not interchangeable for the health of a shrimp, this seems not very logical.


Welcome to shrimpkeeping  It seems based largely around fear, superstition and a halfway grasp on what GH and TDS actually means. I assume some shrimpkeepers actually know that GH =/= calcium, but I think the rest are just doing what they are told and blindly raising GH and TDS to the numbers considered ideal. They are incredibly scared of copper, which yes, copper can be fatal in high doses but shrimp also require trace amounts of copper to be healthy. As usual poison is in the dose..
I think a lot of this stems from the sensitivity of the shrimp, they have been inbred so much that the populations are very delicate and no one wants to rock the boat even the slightest for fear of losing any shrimp. So the care of them becomes an increasingly narrow path to walk, magical products and foods said to be good for them become a must, and no one dares do anything else. 
I havent ventured much onto shrimp forums, mostly because I assume I will be chased out by an angry mob with torches and pitchforks.
Anyway this is a bit off topic now.

I think there is something to the minimum amounts of calcium (and therefore to some degree GH) listed as requirements for the various species. So if you only keep plants I think you can go much lower. But I would personally go for the levels the shrimp want in a planted tank with shrimp. I suspect some of it can be worked around by supplying calcium through food and not watercolumn, but is it a good idea to do it this way?
I would welcome more knowledge on conditions where the shrimp species came from, and maybe shrimp keepers can consider that hardiness can be a good trait to also select for in shrimp populations.


----------



## Nick potts (7 Feb 2022)

MichaelJ said:


> This is an older reference, but may be helpful; some measurements from river tributaries with Bee/Cheery shrimps. Notice the almost universal high Ca and Mg contents.
> 
> Cheers,
> Michael



Interesting PH values for Bee shrimp.


----------



## MichaelJ (7 Feb 2022)

Hufsa said:


> I think there is something to the minimum amounts of calcium (and therefore to some degree GH) listed as requirements for the various species. So if you only keep plants I think you can go much lower. But I would personally go for the levels the shrimp want in a planted tank with shrimp. I suspect some of it can be worked around by supplying calcium through food and not watercolumn, but is it a good idea to do it this way?


I agree.  Personally, I'd rather just add that extra ppm of Ca and carry on.... Relying on food to make up for the low Ca in the water column might work...  but if your already sitting around say 3'ish GH at a customary 3:1 ratio, why not just add that extra 10 ppm of Ca and a few ppms of Mg and be on the safe side.


Hufsa said:


> They are incredibly scared of copper, which yes, copper can be fatal in high doses but shrimp also require trace amounts of copper to be healthy. As usual poison is in the dose..


Yes, there are some pretty hysterical notions about copper out there...  some are  justified, say if you tap water is high on copper (the EPA limit here in the US is 1.3 ppm... which is likely lethal for most fish and inverts) especially at low pH and low alkalinity,  but if not (say by using RO water), and your using a quality trace blend, you're  unlikely to get into trouble.  When I started to drill down to get a conservative sense of the limits where Cu might interfere with the wellbeing of my shrimps  it seems to be somewhere around 0.05 and 0.1 ppm  (at low pH and low alkalinity)...  With the amount of traces I am dosing (which is actually relatively high on Cu vs. other blends), twice per week to target 1 ppm of Fe (EDTA), I am getting about 0.014 ppm of Cu/weekly. If I would be crazy and just assume* zero uptake* of the Cu I am dosing the  point of equilibrium with my weekly 40% WC would be 0.022 ppm of Cu.

Cheers,
Michael


----------



## plantnoobdude (7 Feb 2022)

MichaelJ said:


> Yes, there are some pretty hysterical notions about copper out there... some are justified, say if you tap water is high on copper (the EPA limit here in the US is 1.3 ppm... which is likely lethal for most fish and inverts) especially at low pH and low alkalinity, but if not (say by using RO water), and you using a quality trace blend, you're unlikely to get into trouble. When I started to drill down to get a conservative sense of the limits where it might interfere with the wellbeing of my shrimps it seems to be somewhere around 0.05 and 0.1 ppm (at low pH and low alkalinity)... With the amount of traces I am dosing (which is actually relatively high on Cu vs. other blends), twice per week to target 1 ppm of Fe (EDTA), I am getting about 0.014 ppm of Cu/weekly. If I would be crazy and just assume* zero uptake* of the Cu I am dosing my point of equilibrium with my weekly 40% WC would be 0.022 ppm of Cu.


also, plants uptake a lot more than what they need of these toxic (at some concentrations) metals. so a heavily planted tank can help against micro tox to fish.


----------



## _Maq_ (26 Jun 2022)

Pic B(72): Signs of light relative deficiency of Ca. K : Ca ratio = 1 : 1.
Pic C(72): A healthy plant. K : Ca ratio = 1 : 10.


----------



## JoshP12 (30 Jun 2022)

Many people observe vibrant coloration and better plant forms (tighter internodes) at higher GH up to ~ 7 and paired with KH0 as well. Must tighten up how fast nutrients are absorbed through water column?

Always with rich substrate.

I’d like someone to try 20GH 0KH with rich soil and demanding species so we can see the result


----------



## JoshP12 (30 Jun 2022)

_Maq_ said:


> Pic B(72): Signs of light relative deficiency of Ca. K : Ca ratio = 1 : 1.
> Pic C(72): A healthy plant. K : Ca ratio = 1 : 10.
> 
> View attachment 190366View attachment 190367


Makes sense … it also shows the benefit of using good soil substrate with high CEC and good nutrition — you can get away with less strict water parameters.


----------



## _Maq_ (30 Jun 2022)

JoshP12 said:


> the benefit of using good soil substrate with high CEC and good nutrition — you can get away with less strict water parameters.


I agree that adding clays or zeolites may be beneficial. However, I would not recommend using commercial soil substrates because of their high content of degradable organic substances. Instead, I'd suggest blending silica sand with selected pure powder clays or zeolites. Selected ones, because there are significant differences in their affinity for various cations.
Whether this allows for less diligent dosing of minerals I cannot confirm. But it sounds quite reasonable.


----------

