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Confused about TNC Complete dosage and Mg levels

Tanksy

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7 Sep 2018
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Location
Cambridgeshire
My tank is 30 l and I'm dosing TNC Complete. I've noticed some leaves of my Bucephalandra Pygmaea are a bit pale (yellowish) with green veins. Looked it up and seems like Mg deficiency (?).

IMG_5503.jpg IMG_5501.jpg

According to TNC, the dosage is 1ml/10l/week, but can be x2 or x3 depending on plant growth, WC, etc. So I'm dosing 3 ml 2 times a week.
However, the Nutrient dosing calculator (estimative index) says I should dose 7.5 ml 2-4 times a week.

Should I:
A. Increase the TNC recommended dosage to 9 ml/week ( 3 ml x 3) or even 12 ml/week (3 ml x 4)?
B. Follow the calculator's advice and dose 7.5 ml 3 times a week?
C. Keep the current dosage and supplement with Magnesium Sulphate Heptahydrate (Epsom Salts)?
D. Just do nothing because I'm overthinking it and there's no problem?

Cheers!
 
C. Keep the current dosage and supplement with Magnesium Sulphate Heptahydrate (Epsom Salts)?
Hard to diagnose a deficiency with any accuracy but a good way to rule magnesium out would be to get some magnesium sulphate/epsom salts and add a quater of a teaspoon to your tank, that will raise the mg levels by about 4ppm, if the paleness decreases then "bingo," you've just identified, and cured a deficiency.
If it is a magnesium deficiency you should see results within a couple of days.

Cheers.
 
Hi all,
My tank is 30 l and I'm dosing TNC Complete. I've noticed some leaves of my Bucephalandra Pygmaea are a bit pale (yellowish) with green veins. Looked it up and seems like Mg deficiency (?).
Hard to diagnose a deficiency with any accuracy but a good way to rule magnesium out would be to get some magnesium sulphate/epsom salts and add a quater of a teaspoon to your tank, that will raise the mg levels by about 4ppm, if the paleness decreases then "bingo," you've just identified, and cured a deficiency.
If it is a magnesium deficiency you should see results within a couple of days.
What @John q says.

It looks like it is the new leaves that are stripy? Which makes iron (Fe) and or manganese (Mn) options, as both are <"non-mobile within the plant">. Have a look at <"Slightly sad floating plants">.

Because you have very hard, calcium (Ca) rich, tap water (I know you are cutting it with RO) both magnesium and iron deficiencies <"are more likely">, and you may need a <"different chelator for iron">.

cheers Darrel
 
Thank you all for your replies!

Hard to diagnose a deficiency with any accuracy but a good way to rule magnesium out would be to get some magnesium sulphate/epsom salts and add a quater of a teaspoon to your tank, that will raise the mg levels by about 4ppm, if the paleness decreases then "bingo," you've just identified, and cured a deficiency.
If it is a magnesium deficiency you should see results within a couple of days.

Cheers.
I guess that makes sense. I've already placed the order.

Hi all,


What @John q says.

It looks like it is the new leaves that are stripy? Which makes iron (Fe) and or manganese (Mn) options, as both are <"non-mobile within the plant">. Have a look at <"Slightly sad floating plants">.

Because you have very hard, calcium (Ca) rich, tap water (I know you are cutting it with RO) both magnesium and iron deficiencies <"are more likely">, and you may need a <"different chelator for iron">.

cheers Darrel
It's some of the old leaves that are stripy as shown in the first photo taken from above.
The floating plant is a Salvinia Auriculata. Grows fast and looks healthy. Colour's the same as the first day I bought it.
I've read the thread you linked (different chelator for iron), and I didn't understand a thing! My knowledge in chemistry is very basic.
In case it's not an Mg deficiency, and given that my tank is only 30 l, does it make sense to buy a product like Seachem Flourish Iron?
 
Hi all,
It's some of the old leaves that are stripy as shown in the first photo taken from above.
You can often have issues with both magnesium (Mg) and iron (Fe) in hard water. If it is magnesium (Mg) deficiency you should get a fairly instant greening.
I've read the thread you linked (different chelator for iron), and I didn't understand a thing! My knowledge in chemistry is very basic.
In case it's not an Mg deficiency, and given that my tank is only 30 l, does it make sense to buy a product like Seachem Flourish Iron?
Plant nutrients are only available to plants as "ions", charged particles in solution. As soon as they form <"insoluble compounds"> they go out of solution and aren't plant available. The problem with ferric iron (Fe+++) is that it wants to <"combine with dissolved oxygen"> ("to form rust"), hydroxide (OH-), phosphate (PO4---) and carbonate (HCO3-) ions to form insoluble compounds.

Because of this tendency to go out of solution ferric iron (Fe+++) ions are combined with an organic acid, a chelator like EDTA, which stops this happening. The iron ions are actually so tightly bound by the chelator (FeEDTA etc.) they would be unavailable if the chelator wasn't broken down (photodegraded) by light.

"Seachem Flourish Iron" probably won't help, because it is <"ferrous (iron II) gluconate"> and that isn't a good chelator for iron in hard water. <"Chempak Sequestered Iron"> would work.

cheers Darrel
 
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Hi all,

You can often have issues with both magnesium (Mg) and iron (Fe) in hard water. If it is magnesium (Mg) deficiency you should get a fairly instant greening.

Plant nutrients are only available to plants as "ions", charged particles in solution. As soon as they form <"insoluble compounds"> they go out of solution and aren't plant available. The problem with ferric iron (Fe+++) is that it wants to <"combine with dissolved oxygen"> ("to form rust"), hydroxide (OH-), phosphate (PO4---) and carbonate (HCO3) ions to form insoluble compounds.

Because of this tendency to go out of solution ferric iron (Fe+++) ions are combined with an organic acid, a chelator like EDTA, which stops this happening. The iron ions are actually so tightly bound by the chelator (FeEDTA etc.) they would be unavailable if the chelator wasn't broken down (photodegraded) by light.

"Seachem Flourish Iron" probably won't help, because it is ferrous (iron II) gluconate and that isn't a good chelator for iron in hard water. <"Chempak Sequestered Iron"> would work.

cheers Darrel
Thank you for the informative reply Darrel!
Would one of these 8% Fe DTPA or 13% Fe EDTA work?
 
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@FrankR I do not know for how long you have been growing that Bucephalandra sp, but I can tell you that some sp, for instance Bucephalandra wavy green for example does not appreciate receiving strong/direct light else it starts yellowing and shows those types of veining. In the meantime other Bucephalandra sp couldn't care less, like well known Theia 9 or Brownie Ghost.
 
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@FrankR I do not know for how long you have been growing that Bucephalandra sp, but I can tell you that some sp, for instance Bucephalandra wavy green for example does not appreciate receiving strong/direct light else it starts yellowing and shows those types of veining. In the meantime other Bucephalandra sp couldn't care less, like well known Theia 9 or Brownie Ghost.
It's a Bucephalandra Pygmaea "Bukit Kelam". It is the Wavy Green indeed. Thanks for the tip.
The thing is that I've glued it there. Is there an easy way to remove it?
 
It's a Bucephalandra Pygmaea "Bukit Kelam". It is the Wavy Green indeed. Thanks for the tip.
The thing is that I've glued it there. Is there an easy way to remove it?
Perhaps creating some shadow with a taller plant or a piece of wood? If not possible then I would try my best removing it from where it is and putting it on a less lit area of the tank. If you don't see any similar deficiency in your other plants then it's highly likely that this is caused due to excessive light.
 
Perhaps creating some shadow with a taller plant or a piece of wood? If not possible then I would try my best removing it from where it is and putting it on a less lit area of the tank. If you don't see any similar deficiency in your other plants then it's highly likely that this is caused due to excessive light.
Will do that. Cheers!
 
Magnesium deficiency first shows on older leaves. It looks like lack of sulfur (relative to phosphorus, possibly), but unlikely if your water is hard. So, manganese rather than iron, I bet.
 
FrankR, can I ask if you plan to increase the fertilisation dose of TNC gradually or just going all in based on EL dose?

Sorry to jump on your thread and admin feel free to move this but related to that question I just wanted a quick sanity check on the fert calculator (I'm an ape and relatively new)

I have a 60L tank good light & Co2....It's a column tank so whilst I have planted what I can the real estate at bottom of the tank is limited to 35cm x 35cm so not sure I would class it as heavily planted looking at others posts. I have dwarf sag, crypts, amazon sword, reineckii mini (and a few others but forgot) and will be adding some Java moss to drift wood shortly.

I have been dosing TNC @ 1ml daily to be just above the standard dose as advised by the company (7ml weekly). I want to up this since the plants have grown (slowly) hence looking at the el dosing equivalent and easier for me to do this daily for memory sake. So far Algae is under control a bit of green hair algae on a few leaves but not spreading. (increased waterflow and Co2 distribution via in-line).
On the EL Daily (fert calculator), it states 7.5ml for 60l, is that per day!? (52.5ml weekly)....on the standard EL calc it states 15ml 2-4 times per week (assuming 4 times = 60ml? )...So I'm in the 50-60ml weekly range.
Would such a large increase in fertiliser cause a big imbalance at this stage? Am I supposed to up things gradually and check for algae growth? I re-scaped about 2 months ago. I do at least one 50% water change & most likely 2 per week. Thanks in advance. for any help offered.
 
My tank is 30 l and I'm dosing TNC Complete. I've noticed some leaves of my Bucephalandra Pygmaea are a bit pale (yellowish) with green veins. Looked it up and seems like Mg deficiency (?).

View attachment 189922View attachment 189923

According to TNC, the dosage is 1ml/10l/week, but can be x2 or x3 depending on plant growth, WC, etc. So I'm dosing 3 ml 2 times a week.
However, the Nutrient dosing calculator (estimative index) says I should dose 7.5 ml 2-4 times a week.

Should I:
A. Increase the TNC recommended dosage to 9 ml/week ( 3 ml x 3) or even 12 ml/week (3 ml x 4)?
B. Follow the calculator's advice and dose 7.5 ml 3 times a week?
C. Keep the current dosage and supplement with Magnesium Sulphate Heptahydrate (Epsom Salts)?
D. Just do nothing because I'm overthinking it and there's no problem?

Cheers!
I was observing similar deficiencies on exactly the same plant in my last high energy scape. I was using APF DIY ferts dosed using dosing pump so 100% consistent dosing. But this deficiency was coming and going and sometimes new leaves were developing holes. I think this was happening due to inconsistent CO2 when stem plants were taking over the tank and filter was due the cleaning.
 
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