Latest insights on Calcium

[Yugang]

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 Are these views from very educated plantkeepers now considered outdated?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]

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?

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]

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]

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.

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]

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]

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

 

[MichaelJ]

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]

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]

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]

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]

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]

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.

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]

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_]

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]

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]

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_]

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.