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Old 10-16-2005, 06:52 PM   #21 (permalink)
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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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Old 10-21-2005, 07:35 PM   #22 (permalink)
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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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Old 10-22-2005, 07:43 AM   #23 (permalink)
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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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Old 10-22-2005, 12:27 PM   #24 (permalink)
 
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Quote:
Originally Posted by Edward
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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Old 10-22-2005, 01:10 PM   #25 (permalink)
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Quote:
Originally Posted by plantbrain

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.

[quote] 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.

Quote:
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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Old 10-23-2005, 06:41 AM   #26 (permalink)
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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

Last edited by Edward; 02-17-2006 at 01:55 PM..
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Old 12-30-2005, 12:52 AM   #27 (permalink)
 
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Quote:
Originally Posted by dennis
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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Old 01-28-2006, 08:31 PM   #28 (permalink)
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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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Old 01-28-2006, 08:51 PM   #29 (permalink)
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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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Old 01-28-2006, 09:03 PM   #30 (permalink)
 
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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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