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So I now, theoretically, have 95ppm Ca and 15ppm Mg.

What do you recommend I do now and in the future? If my tap readings are correct, I will want to start adding Mg eventually correct, but not for a while. I assume that with those numbers I don't need to worry about K. I add 25+ppm K each week with with my Macro additions.

Bahhhh, why does this confuse me so sometimes.
 

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Hi All

The Rotala wallichii been growing well at 20 ppm Ca and 2 ppm Mg. However, it stops growing when Mg changes to 10 ppm. When conditions change back to 2 ppm Mg the plant starts growing again. Please see the picture.



This test I have repeated several times. Please take in consideration that the Mg is from MgSO4, not MgCO3. The Ca is from CaSO4 and CaCl2, not CaCO3 nor CaNO3.

Thank you
Edward
 

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Thats interesting that you show that for an example. I have Mayaca fluvitalis, a plant with very similar leaf and growth patterns to Rotala wallachi, that exhibited these same growth patterns when I was having all my issues. the growth has returned to normal since switching to Flourish, adding Ca and many water changes. Basically increasing the Ca and decreasing the Mg concentrations in the tank water.

Question is: are the improvments a result of higher Ca, lower Mg or both?
 

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Edward said:
Hi All

The Rotala wallichii been growing well at 20 ppm Ca and 2 ppm Mg. However, it stops growing when Mg changes to 10 ppm. When conditions change back to 2 ppm Mg the plant starts growing again.
This test I have repeated several times. Please take in consideration that the Mg is from MgSO4, not MgCO3. The Ca is from CaSO4 and CaCl2, not CaCO3 nor CaNO3.

Thank you
Edward
I'll give this a whirl.
I like the Rotala and it does grow back fast when happy.
What might be interesting is focusing on the KH vs Mg.

I know many folks that have rather high GH's, many from dosing SeaChem Eq and in a number of cases they have Mg over 10ppm but an associated higher level of Ca as well.

Ca/K/Mg/NH4 blocking all appears to need to be much higher concentrations typically found in pore water to start to get blocking. But species to species difference may play a larger role.

I have found the Luwigia cuba to stunt much like the R wallichii in the hard KH/GH's, but teasing apart which is causing what requires more grow out and then changes to the Mg, KH and Ca levels.

In general, if there is a GH issue, lower Mg is typically the reason if the GH is already high, it's virtually unheard of to find high Mg and low or limiting Ca levels if the Gh is 3-5 degrees or high.

Many folks have high GH's and does well with Rotalas and Ludwigia cuba.
It might be evidence of a ratio being important even at low concentrations.

Regards,
Tom Barr
 

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plantbrain said:
In general, if there is a GH issue, lower Mg is typically the reason if the GH is already high, it's virtually unheard of to find high Mg and low or limiting Ca levels if the Gh is 3-5 degrees or high.
This may be true but it could be a dangerous way of thinking. This statment considers natural water sources. Our tanks have the potential to be anything but natural. In my case, I was doseing for several months a trace that contains higher Mg but no Ca. I was dosing no other source of Ca, except via water changes.

Here is where i assume there is a catch. At the time of my tank issues, my water supply changed, as it often does in the dry summer months when the town changes to a different source. My tap kH goes from 4-5 to 0 and the Gh changes from 8-9 to 12+. Why, living in the New England area of the US, would I have a 0kH from a natural source? I wish I knew what my Ca/Mg was form this time but I had no way to test then. If 0kH is possible why not high Mg, low Ca? That is not sarcasm, that is a seroius question. Could the water company be somehow filtering/treating the tap and affect these conditions? Contacting my local water company is an exercise in futility.......

For probably 3 months in the summer I was dealing with the different water parameters and towards the end, these difficiencies. Also, I switched to CSM in April, that is 5 months for the MG to build up in relation to the Ca. This tank gets a 40% wc weekly. Just my observations.

Many folks have high GH's and does well with Rotalas and Ludwigia cuba.[/quote

I have not really had issues with rotalas but my L. Cuba was stunting heavily mid-late summer. After my water supply went back to normal and I started adding 1/8tsp Seachem Equilibrium at wc, it has been growing gang busters. Probably for the last month or so.

It might be evidence of a ratio being important even at low concentrations.
I thought you always say ratio does not really matter as long as the Gh is over 3-4 ;) Just yankin your chain!
 

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Hi Dennis
let's not confuse Total Dissolved Solids TDS with concentration in ppm.

A TDS meter measures electrical conductivity or resistance of a solution, whichever you understand better.

1 / resistance = conductivity
1 / conductivity = resistance

Pure water = low conductivity and high resistance.
Impure water = high conductivity and low resistance

Resistance in Ohm
Conductivity in Siemens

We are still talking electricity here. So why is your tester calibrated in ppm? This is where the confusion comes from. TDS testers calibrated in ppm instead of Siemens. Someone had this idea to use NaCl or kitchen salt solution to display in ppm. It may work better for some applications but not for aquariums and water works.

How to get out of this mess? We can get approximate result back to conductivity value:
uS = 2 x ppm
ppm = uS / 2

MicroSiemens [uS] is the right way to talk about water TDS, however, every element conducts electricity in a different rate so there is no way to tell what elements are in the solution.

Edward
 

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dennis said:
This may be true but it could be a dangerous way of thinking. This statment considers natural water sources. After my water supply went back to normal and I started adding 1/8tsp Seachem Equilibrium at wc, it has been growing gang busters. Probably for the last month or so.

I thought you always say ratio does not really matter as long as the Gh is over 3-4 ;) Just yankin your chain!
They don't, but your new routine adding a little bit of SeaChem Eq each week will address the issue(which is Mg limitation), we found this out about 10 years ago in the Bay area using this product.

Many thought it is was all the K+, which was all the rage back then.
Some thought it was the Ca, Steve Dixon wondered if it was the Mg. He's alos the guy that found out I had such high PO4.

He had so many things right on looking back, too bad he's not active any longer.

I'm about ready to torture some wallichii also. Bring on the salts!

Regards,
Tom Barr
 

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Dennis,

I just read this post and noticed that you were having some issues with GH: Ca / Mg ratio. Seemed like Seachem Equilibrium helped, no ?

Why going with Greg's GH Booster now ?
 

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I am not exactly sure what my issues are but I do belive it is Ca or Mg deficiency. I will be testing the addition of each nutrient seperately before I try the Greg's/Tom's booster;) Equilibrium seemed to help before although I have no difinitive proof. I would like more this time.

As for why the change; I was ordering from Greg anyway, its cheaper and the Equlibrium is hard as a rock and doesn't seem to dissolve that well. I don't entirely trust any powdered material that I can't stir up as I don't know how well it is mixed or why it is hard. I literally have to scrap off small bits with a metal spoon to use what I have. I also know Equilibrium has lots of K and I am hoping the Booster has less, although I have not done the math yet to figure it out. Thats a project for tomorrow when I am less sleepy.
 

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Most salts will absorb water and become rock hard rapidly, that's why they add rice to absorb water vapor to salt shakers.

I'll do some measurements for the GH booster, dang, i hate it when my name gets attached to something:)

It's Greg's Creation inferred from something I wrote at one point.
It should have the same effect as SeaChem Eq if used the same although it has less K and more Mg if he used something I said.

You have weird tap, one of the few that has high Mg.
This is a good thing though, you can see what impact high Mg has on plants.

Edward's example did not look good:)
But you never know.

I've had all sorts of Ca levels and K levels etc, I suppose I can really max the Mg out, I've been meaning to anyway.
Done most of the others.

I've never found any evidence of a ratio based issue though with Ca/Mg/K to date in any research. As long as they are non limiting and not extremely high, they do not impact crop production. I typically look at rice studies since they are the huge ag crop that is also an aquatic plant.

Regards,
Tom Barr
 

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Searching for research about rice, thats a real good idea!

The photo Edward posted looks like the issue I used to have with Mayaca fluvitalis and others. Now I have the same stunting issue with Rotala najanshen, Posogtemon stellata and occasionally with Rotala green and Hemianthus micranthemoides. The new leaves of Anubias barteri ver nana Petite exhibit some holes, occasional yellow dots, etc and new growth on Pogostemon helferi has some pure white areas. I would be inclined to believe you that it is low Mg (you should certainly know better than me) but for the fact that th eissue is strictly with new growth. Ca is immobilbe while Mg is mobile, correct? If it was Mg shouldn't the issue be with old growth?

50 gallon tank,1.4wpg-2hrs, 3.64wpg-5hrs, 1.4wpg-4hrs. NO3, PO4 and traces are all dosed in excess 10:.5ppm NO3:pO4-4xweek and moderately high fish load. Traces= 45ml Flourish week+15ml Flourish Fe. CO2 added via diffuser until fish stressed.

The way I read it there are 3 possible causes for this issue:
-high or low Mg
-Low Ca
-low K

To be honest I am not certain my water test reading were accurate last time; seems there was some confussion with the TDS, Ca reading, CO3 equivilant, etc.

I am trying to do it right this time. I have ordered Lamotte Ca and kH/Alk test kits. I will callibrate my current Aquarium Pharmacuticals Gh and kH test kits (see see post 5 here http://www.aquaticplantcentral.com/forumapc/showthread.php?t=10305 )

I need to do a wc and basic maintainance tomorrow. Before the wc I will take several samples in cleaned, 12ml test tubes and cab with saranwrap, parafin sealing film then a cork. I will take several after the wc also as maybe the stunting is occuring early in the week and maybe later in the week? (I though it is possible that the wc is either adding enough of a nutrient fo rgrowth early in the week but that become deficient later; or, the wc is removing something that my pH6.4-6.5 is dissolving from the substrate) I have planty of tubes so its no biggie.

I will test these samples once I get my kits and report back.

In the mean time, what to do? I want to start adding CaCl2 now, say 15ppm? (that would be about the equivilant of raising the GH 2 with Booster/Eq) after the wc as I don't like the poor growth.

Could it be low K? I add ~26ppm weekly through my KNO3/KH2PO4 dosing. Unless it is in my tap I would not get it any other way.

Oh yeah.. I can grow Tonina, Ludwigia cuba, P helferi, and HC just gang busters. :p

Any thoughs on my thoughts are appreciated, from anyone.

(I have a Soils class with a lab this semester..wonder if they have any fun equipment?)
 

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I would be inclined to believe you that it is low Mg
I guess this is not that important, but i thing Edward is having problems when the Mg levels gets to high.
 

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NE,

Reciently, in other threads Tom has posted that my issues are probably low Mg. What you quoted me as saying is part of a statement where I was saying that while I know I should believe someone with as much experience as Tom, for some reason low Mg does not make sense to me for this. I agree that high Mgandn low Ca could be an issues. Now I need to test that:)

Sorry for any confusion.
 

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OK, sorry i thought it referred to Edwards post.

I'm very interested in this as well.
I have had major problems with stunting, now i add Mg and Ca and it seems better but i dont know what levels i should have as target to get the best growth.

It's going to be very interesting to hear about your conclusions.
 

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Hi gang... there are two plants giving me similar issues, L. "Pantanal" and sometimes R. macrandra "green". The rotala surpises me a bit since it used to grow really well for me. What will happen is that occassionally, early week after a WC it would stunt, then later in the week would have nice growing shoot sent out already, but not as prounced as what Edward posted. I've tried a few things and seem to have it under control, at least with the rotala. I basically starting going to 1/2 RO 1/2 tap, and switched back to entirely TMG as a trace, 2ml/day per 10 gallons, 6 days a week. Rotala is now fine - now I'm working on the Pantanal.

I tried elevating both Mg and Ca in the proper ratios, that didn't help, also adding more Mg didn't help. So now I'm trying two weeks of elevated calcium, if I forget to update the thread please PM me and I'll post results. Everything else in the tank is growing fine so its a matter of getting some of these fussier plants to stay happy.

Jeff
 

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Would it make any difference if the Mg is in chelated form? I've noticed that some hydroponic growers use the chelated form even though MgSO4 is much cheaper...
 

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There's no need to chelate Mg, but Mn is another matter.
Typically in traces, Mn as well as Zn, Cu, are chelated, EDTA.

Regards,
Tom Barr
 

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OK chemistry people:

I just got a LaMotte Ca test today and 2 runnign 2 tests I get the same answer of 95ppm Ca, read as ppm Calcium Hardness as CaCO3.

In the following equation used to find the ppm of Mg, does the Ca in ppm number need to be converted from my reading of 95ppm as CaCO3? If so, I would divide by 7.143?

GH in ppm - (2.5*Ca in ppm)
--------------------------- = Mg in ppm
4.1

Any help is appreciated!
 

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JLudwig said:
Hi gang... there are two plants giving me similar issues, L. "Pantanal" and sometimes R. macrandra "green". The rotala surpises me a bit since it used to grow really well for me. What will happen is that occassionally, early week after a WC it would stunt, then later in the week would have nice growing shoot sent out already, but not as prounced as what Edward posted. I've tried a few things and seem to have it under control, at least with the rotala. I basically starting going to 1/2 RO 1/2 tap, and switched back to entirely TMG as a trace, 2ml/day per 10 gallons, 6 days a week. Rotala is now fine - now I'm working on the Pantanal.

I tried elevating both Mg and Ca in the proper ratios, that didn't help, also adding more Mg didn't help. So now I'm trying two weeks of elevated calcium, if I forget to update the thread please PM me and I'll post results. Everything else in the tank is growing fine so its a matter of getting some of these fussier plants to stay happy.

Jeff
Probably CO2 then.

Rotala's love it when it's high, a little drop off and you'll get stunting.

I think that is the main issue with many folk's stunting issues and certain species issues.

They see one thing and incorrectly attribute it to Mg or Ca.
I'll suggest adding most every nutrient to excess, that is relatuively easy to do.

From there all you do is tweak CO2.
This is the best method to get good growth for folks.

We can add known amounts of Ca/Mg/NO3/K/PO4/etc, then adding CO2 is all that is left.

We can gauge the max amounts that might be needed by other folk's parameters for the same plants.

From there, if those match up, CO2 is the only thing left.

I see too much confidence in folk's reports of CO2 levels and reports of very wide ranges of CO2 ppm readings for it NOT to be a huge issue.

I'd say many/most of the Ca/Mg issues are CO2 related.

Regards,
Tom Barr
 

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So does shutting of CO2 at night affect plants? Mine comes on with the first bank of lights, (I get about a .3-.4pH shift between lights off and lights on) and CO2 is added 'til the fish HATE me!

I just finished testing my water parameters with Lamotte and calibrated test kits:

GH-
Tank-7.5 (134ppm)
Tap- 6(107ppm)

Ca as CaCO3-
Tank- 95ppm
Tap-80ppm
alternately Ca as elemental
Tank-38ppm
Tap-32ppm

So Mg elemental:
Tank-9.5ppm
Tap-6.6ppm

Yet still I get stunting of Rotala green, R. najanshen, Pogostemon stellata and Anubias nana Petite but not A.coffeefolia or A. nana.

Of course, adding CO2 tillI get fish stress may not mean I have high CO2 but low O2. Calibrated monitor, no electrical interference, says 6.5 with a positive kH of 5. Only way my CO2 could be off is if my pH is affected by PO4 or some organics but I have a fairly clean tank and little wood(manzanita). As for O2, I have a good amount of surface movement and good tank circulation. There is no fish stress in the morning, only during mid photoperiod once the CO2 has been on for some time and the pH has dropped to 6.6-6.5.

So know whats wrong?

kH 5
 
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