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What about issues of Mg blocking Ca. I switched from Flourish to CSM+B several months ago and since then I have had many issues I contributed to trace defficiency. In the end I was dosing 6ml, 3x week, of the standard CSM+b solution to a 15 gallon, high light tank. Macros were dosed 4x week with 10mg/l NO3 and 1.5-2 mg/l PO4. Eco/onyx substrate, high fish load and press CO2 in the 25+ range. I also have a 10, similar setup and dosing but I dose 4-5ml CSM+B 3x week.
All my tanks run a Gh of 9+ and generally a kH of 3+
Even with all that trace I was seeing deficiencies of leaf curling, tip stunting and necrosis on the stems with plants, including Rotala vietnam (similar to wallachi in apperance and growth patterns) H. micranthemoides, Ludwigia arcuata, Hedoytis sp Rio, Mayaca fluviatalis, P stellata narrow leaf and even sever curling and white spots on new growth of Anubias nana and petite. A question posted here to APC lead to a response (by Phil Edwards) that the high Mg levels in CSM might be causeing a Ca blockage/deficiency. Not having any other trace to use, nor a local source for Flourish (*my favorite) I tried a quick fix of dosing 1 drop per gallon/per day of Kent Concentrated Liquid calcium. With in 3-4 days i was noticing signs of improvment. I did not change any other parameters during this time. I cut the liquid calcium and started adding 1/4tsp of Seachem Equilibrium. I now occaionally see small signs of stunting in my anubias, P stellata and HM but only on the occasional stem, not 3/4 of the bunch like before. All my other fine leaved plants succumed and were lost by this time. I attrubute most of my trace issues now with the high Mg, Ca and K that have to be in my tank by now. I need to get away from the CSM i think;)

Also, for some reason I can't seem to keep Nerite snails for more than a few weeks. Could it be related to the hardness ions?

What are ya'lls thoughts on this?
 

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Bert, in short, I don't know the answers to any of your questions. I can't find a Ca test locally that will work for freshwater so I have no idea of my hardness ratio. I don't think it is Mg deficieny as I though Mg would show up on older leaves. My issues all happen to new growth. Also, I know that my original fertalizing (with the CSM) added plenty of Mg but no Ca to speak of, hence my reasoning behind the Mg excess/Ca deficency. Adding Ca seems to have cleared up 90% of the problem. I have some Flourish on the way and will see how things look after using that for 2-3 weeks. I do notice the Gurus recommend Flourish or TMG but not CSM.
 

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Bert H said:
Dennis, I am curious if you have ever determined how much of your gh is from Ca vs Mg? In my case I have a gh of 11, and kept seeing curling stunting on and off on my A. reinickii. So I bought a Ca test kit and found most of my gh came from Ca. I started adding Mg and saw improvements, with still the ocasional stunting. I got some aromatica recently and am having a heck of a time with it - growing real slowly, older leaves getting pinholes and stems rotting. So I am in the process of gradually increasing the Mg to see if it helps. Do you know at what point (Ca/Mg ratio) is it you see inhibition?
Well I was finally to check my waer chemistry today. TDS from Hanna meter and Ca levels from Salifert test

Tank: Tap:
TDS 264 ppm TDS 96ppm
GH 12*= 213.6ppm GH 8*=142.4
Ca 150ppm Ca 120ppm
Mg 63ppm Mg 22ppm

That means that my tapwater has pretty good parameters but my tank water is out of wack due to, I assume, my heavy dosing of CSM and the use of and Onyx/Eco mixed substrate.

Also, can the tap measurments be correct? Is it possible to have a Gh higher than your TDS?
 

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So, in my tank I have 60:15 Ca:Mg, or 4:1. That is perfect now. Guess maybe that is why my stunting is 90% gone. this change probably happened in th elast 2 weeks since switching to Flourish and doing a few wc's with water that has a 9.6:1 ratio. That has probably helped balance things out a bit.

Now there is only one problem. Silly me, I just went and dosed 35ppm Ca. I added 20 ml of Kent's Liquid Calcium. I figured I needed 100ppm of Ca, based on my previous post of 150ppm Ca and 63ppm Mg, to bring my ratio up to the correct amount. I figured adding about 1/3 this week would be a good start in the right direction.

Nuts! Think that will hurt anything?

Oh, and BTW....in my 12 degree hard water, I am growing Rotala sp, formerly known as Ammania Bonsai, Downoi, P. stellata and Ludwidia Cuba with beautiful success. The plants I was having stunting issues with before were P stellata, Anubias nana, H. micranthemoides and Mayaca fluvitalis.

guess I won't have calcium issues for a few weeks huh;)
 

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I would be inclined to agree with your Shalu except for 2 things. First, I don't know what my parameters were a month or 2 ago whe this issue was real bad, but I do know I was dosing heavily with CSM+B, a product that contains lots of Mg but almost no Ca. I was not adding Ca or Mg from any other source except water changes. Secondly, the issue I had with m y plants was easy to see in the Anubias leaves. New growth only was affected and the problems were litght spots, curling and holes in the leaves. Mg is a mobile nutrient, meaning that plants will take it from old growth to feed new growth when there is a deficiency No plants in my tanks exhibited issues with old growth.
 

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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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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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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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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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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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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 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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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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Tom,

That's the first time I have ever seen you do math! Not that you don't do math, just never seen you type it all out. Now I feel special :)

Jeff, you pring up a good point regarding using a pH shift rather than kH to measure CO2. In my case, fully settled tank water is 7.0 but by 6.5 fish are gasping. This stress does not happen right before lights, and CO2, come on, as I would expect but rather midday once the CO2 has been cranking for a couple hours. The increased lighting period I run midday creates some extra O2, visable as heavy pearling, but this obvious sign of O2 saturation does nothing to alleviate fish stress. I can only assume from this thathigh CO2 levels are to blame. However, this does not explain the only .4-.5 pH drop the tank can handle.

Incidently I use the intank diffuser method with lots of mist.

I think I may have to do some mucking with surface movement but anymore turbulance and I will get whitecaps!

Tom,

Thanks for all your help with this. It seems that my water parameters are definately within the limits with nothing excessivly low or high, much as you assumed it would be. I may try just adding some GH Booster or Equilibrium but I really wanted to pinpoint this, if for no other reason than personal satisfaction!

Jeff, I orignally though via other's suggestions that possibly I had a high Mg affecting Ca, as unlikely as that was. Plus, the fact that only new growth and not old growth was affected pointed to immobile nutrient deficiency. However, providing I have calibrated my GH test correctly and done all the math correctly, my Ca and Mg are definately in good shape.

So, what are our other options....
a)faulty test readings
b)CO2 fluctuations/limitations Do you turn off the CO2 at night?
c)Toxicity of some trace element
d)Low K
e)Low some other trace

Any other possibilities?

Oh, and
And the whole exercise is a bit pathological as I would easily sub in one of the 300 other plants I can grow well :smile:
But that would mean admitting defeat! :)
 

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JLudwig said:
Dennis I use a JBJ solenoid so its only 12 hrs of CO2 a day. I could run the CO2 all night and see what happens, when I had no trouble with the rotalas (I've got the plantfinder picture of the same plant giving me guff right now, go figure :) ), I was on a 24 hour cycle. Hmmm....

With respect to your problem I would get to the bottom of that pH issue ASAP. Something is wrong with your pH measurement, it sounds like the gain on your instrument might be out of whack. When was the last night you bought a new probe?

Low K? Don't know, K is immobile IIRC so not sure that would cause stunting in new growth.

Jeff
Jeff,

Yes, the pH/CO2 issue has become my new priority. I tried cranking the CO2 a bit more by lowering the set point of my monitor down a little. I also increased the surface flow a little and added a PC fan to my hood to try and promote air movement over the water's surface, there by increasing O2 and reducing fish stress from adding more CO2. All the fish were alive when I got home tonight but that does not mean they were not stressed while I was gone. Lights have been off for about 2 hours and pH is 6.6.

I have not replaced the probe in about 1.5 years (technically never replaced the probe as I bought the unit new then). I have observed the readings with lights on, lights off, in fact with all power to the aquarium off save for the controller itself. Never a change in readings and I have done this several times, once very reciently. The probe calibrates very easily, never straying more than .1 in a month and always tests right to 7(or 6.9 depending on how long it was since last calibrated) when checked with a new sachet of pH 7.0 calibration solution. I have checked this and checked this and checked this and it does not seem as though the probe is bad. I even once tried sealing the probe up in a sachet for several hours to see if it wandered then...nothing. I suppose I could get a new probe but at $50... I may try running without the controller and just go by bubbles count and observation.....

Any recommendations for a starting bubble count on a 50 gallon, lots of surface movement and in tank ceramic diffuser?

From my reading K is mobile so low K would not affect new growth; however, I have also read that low K can reduce uptake of Ca, not block but reduce through slowed growth. K is also major in root development and stomata regulation (I think). I have noticed a signifigant decrease in root development in most of my plants over the last couple months, especially Bylxa japonica, which was usually a strong rooter, HC, aswell as Lobelia and stems like L cuba and P stellata, which used to produce extensive roots. There are no "aerial" roots comming form the Rotala's. My tank gets 4x week dose of 10:6:.5 NKP via GW ferts, or 40ppm NO3, 24ppm K and 2ppm PO4. I know I am dosing that so it doesn't seem like low K is an issue, nor low Ca, nor low Mg, or high Mg..... Also, the lowered rooting could be that the tank is more mature now and the plants not needing to resort to substrate nutrients due to plenty of water column nutrients. I just don't know.

Must be a CO2 thing:(
 

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Well,

I ate some crow Thursday, boy was it good. I saw the sticky in the equipment forum about testing pH probes. Turns out mine must be bad. Only hit about 8.5 in the Windex, soaking an alcohol and then rinsing/recalibrating only made it worse. It tested immediatly to 7.o in the bufer solution though.

Fool me once, idiot:)

So I increased surface movement as much as possibe, I'll not get more without using an extra powerhead but Eheim 2217 on a 50gallon should be sufficient! I also added a PC fan blowign across the surface of the water thinking I may not have been gettign good air diffusion in my canopy. Lastly I cranked the CO2 even more.
 
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