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Maq's low-tech troubles

Hi all,
That looks really nice, such beautiful rounded green leaves 😍
I must try to get my greedy paws on some of this species. This is not the golden version right? I think the green variety looks nicer, but it seems less common 🤔
It might be native to Norway? It is frequent in the UK, but doesn't really grow in wet places, usually in semi-natural grassland in slightly shady places. I'm away at the moment, but there is lots of it on campus.

Cheers Darrel
 
It might be native to Norway?
It might! I was looking for the norwegian name because I thought a garden center might have it. But they didn't. Ill keep my eyes open for it though 😃
For some reason I thought maybe the local wild plants might not like aquarium temps as much as the hobby strain? But then again I hear the latter likes it cool as well so maybe it doesn't matter.
 
It might be native to Norway?

Well, we have a lot of Lysimachia nummularia - including the Aurea variant - here in Minnesota... They are not native, but came in from europe, just like the Norwegians which we have a lot of as well in Minnesota btw. - including myself along my moms family tree... :) in some states they are considered invasive... the Lysimachia nummularia , that is - not the Norwegians... :lol:

I am actually surprised of how many aquatic plants, commonly found in the hobby, that grows pretty far north in the US....

Cheers,
Michael
 
Hi @_Maq_ can you elaborate a bit on this insight... I am reading it as: for a certain amount of x micros (i.e. say you're using 0.5 ppm/wk of Fe as a proxy) you will need a certain amount y of phosphorus... I assume to stimulate uptake... assuming my understanding is correct; is there a rule of thumb - say a ratio - that goes with this in your experience?
My way of dosing micros based on Marschner
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Marschner's Mineral Nutrition of Higher Plants provides a chart indicating relative uptake of nutrients required for a healthy growth. You can see key numbers in red in column "P eq.". Beware, the numbers are in moles. So, if plants uptake one molar unit of phosphorus (or phosphate - it makes no difference in moles), they need 0.03 molar units of boron or iron, 0.015 molar units of manganese, etc.
But you, like most non-chemists, prefer weight units, like mg/L = ppm. Let's translate moles into mg/L. If you dose 100 µM phosphorus, which means 9.50 mg/L phosphates, then plants need to uptake 3.00 µM iron, which returns 0.1675 mg/L iron. And so on.
If you dose 1 mg/L phosphates, plants will require 0.0176 mg/L iron.
Alternatively, if you dose 0.1 mg/L iron, corresponding phosphorus uptake would be 5.67 mg/L phosphates.

I stress that these numbers refer to net uptake by plants. To reach that, we need to overdose some nutrients. There's little worry about boron and molybdenum, they don't tend to get lost. On the other hand, iron losses are always significant because iron readily reacts with mere oxygenated water. The remaining metals (Mn, Zn, Cu, Ni) stand somewhere in the middle; they may or may not precipitate in various compounds. The risk is always higher in basic, alkaline, and generally lushly mineralized water.

To the very right I've added an example showing how I dose micros in my tanks. You can see, only 0.38 mg/L phosphates per week. Low-tech, lean dosing. Ideally, if there were no losses, I could dose corresponding 4.000 P.eq. "units" of iron and other micros. Yet my practice showed that that's not sufficient. So, I overdose iron (10 P.eq. units) and slightly overdose the other micros, too. (I never use Mo and Ni as it makes no sense, even in my RODI water, traces of these metals are present, and that's enough.)
I do not pretend that my numbers are valid for everyone, in any circumstances. It works well for me, but conditions in many tanks are very different. Still, I consider Marschner's ratios a starting point for every tank. Like I said, iron regularly needs to be overdosed, the more so if bicarbonates (and phosphates) are abundant, which is often the case in hi-tech tanks with EI dosing. Yet overdosing non-toxic iron should NOT lead to overdosing other micros (which happen to be toxic). Their behaviour is different and risk of precipitation is remarkably lower.
 
What would be, based on your understanding, the maximum concentration of these toxic micros to be added in an aquarium context? With a healthy safety margin.
 
@LMuhlen , that's a question for a large comparative study. We have seven elements on one side, and bacteria, algae, plants, snails, shrimps, and fish on the other. For any of them, toxicity of any of those elements differs. I don't want to throw any numbers just out of my (indeed imperfect) memory here.
 
I see. Then let me rephrase it into something possibly simpler to answer. What do you think are the micros that people are more prone to have toxicity issues when dosing micros in a tank, considering only toxicity to plants? Which element is more dangerous?
 
For plants, toxicity descends like this: B = Cu > Ni = Zn > Mn > Fe = Mo. For copper, I've noticed a claim that 0.1 mg/L is lethal for plants (any? some?).
 
My way of dosing micros based on Marschner

I am trying to understand this better in terms of ratios we might possibly could recommend as a guide for micro dosing (using Fe as a proxy) relative to PO4 dosing, but I am not sure that would be an easy feat as you would have to consider other critical water parameters such as pH, alkalinity and general hardness.

In any event, in one of my tanks the PO4:Fe ratio comes out as (0.25 / 0.055) = 4.5:1 (this is from Tropica Specialized, P being 0.08, equivalent to ~0.25 PO4 ).
Your "Maq's example" is (0.38 / 0.0168) = 22:1
Straight up Marschner is (9.5 / 0.1675) = 56.7:1

Cheers,
Michael
 
For plants, toxicity descends like this: B = Cu > Ni = Zn > Mn > Fe = Mo. For copper, I've noticed a claim that 0.1 mg/L is lethal for plants (any? some?).

In the case of Cu, 0.1 mg/L is lethal territory for all invertebrates (Shrimps, snails etc.), many fish and probably a lot of bacteria - more so in acidic water - worry about those waaaay before your plants :) Zn, Ni is not much better but the tolerance level for livestock is higher. The devious thing about some of these trace metals is that they can accumulate fairly easily, say in the substrate, if your water is near or above neutral - and if you over a short period of time lower your pH you can have a sudden release that will wipe out your shrimp population in a matter of days. This is something I only realized recently and probably could explain many of those "sudden mass deaths" among shrimps we sometimes get questions about here on UKAPS. Well, the beautiful thing about lean - as we both believe in - is that you really don't have to worry about getting into that trace level territory.

Cheers,
Michael
 
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you can have a sudden release
I suspect it happens quite often. Increased presence of toxic elements is usually beyond hobbyists' capabilities to prove, and signs on plants are equally difficult to discern. A tank simply falls into trouble and no one can tell the reason.
Take boron, par example. Fish tolerate it quite well (just like humans), unlike plants. It's highly toxic for bacteria and fungi; it's used as antiseptic in medicine. If you're forced to dose increased amount of iron, and use a blend of micros as a remedy, you can reach the level where boron gets acutely toxic for (some) bacteria. The result can be quite devastating, the chance of revealing the cause minimal.
 
so
My way of dosing micros based on Marschner
View attachment 206029

Marschner's Mineral Nutrition of Higher Plants provides a chart indicating relative uptake of nutrients required for a healthy growth. You can see key numbers in red in column "P eq.". Beware, the numbers are in moles. So, if plants uptake one molar unit of phosphorus (or phosphate - it makes no difference in moles), they need 0.03 molar units of boron or iron, 0.015 molar units of manganese, etc.
But you, like most non-chemists, prefer weight units, like mg/L = ppm. Let's translate moles into mg/L. If you dose 100 µM phosphorus, which means 9.50 mg/L phosphates, then plants need to uptake 3.00 µM iron, which returns 0.1675 mg/L iron. And so on.
If you dose 1 mg/L phosphates, plants will require 0.0176 mg/L iron.
Alternatively, if you dose 0.1 mg/L iron, corresponding phosphorus uptake would be 5.67 mg/L phosphates.

I stress that these numbers refer to net uptake by plants. To reach that, we need to overdose some nutrients. There's little worry about boron and molybdenum, they don't tend to get lost. On the other hand, iron losses are always significant because iron readily reacts with mere oxygenated water. The remaining metals (Mn, Zn, Cu, Ni) stand somewhere in the middle; they may or may not precipitate in various compounds. The risk is always higher in basic, alkaline, and generally lushly mineralized water.

To the very right I've added an example showing how I dose micros in my tanks. You can see, only 0.38 mg/L phosphates per week. Low-tech, lean dosing. Ideally, if there were no losses, I could dose corresponding 4.000 P.eq. "units" of iron and other micros. Yet my practice showed that that's not sufficient. So, I overdose iron (10 P.eq. units) and slightly overdose the other micros, too. (I never use Mo and Ni as it makes no sense, even in my RODI water, traces of these metals are present, and that's enough.)
I do not pretend that my numbers are valid for everyone, in any circumstances. It works well for me, but conditions in many tanks are very different. Still, I consider Marschner's ratios a starting point for every tank. Like I said, iron regularly needs to be overdosed, the more so if bicarbonates (and phosphates) are abundant, which is often the case in hi-tech tanks with EI dosing. Yet overdosing non-toxic iron should NOT lead to overdosing other micros (which happen to be toxic). Their behaviour is different and risk of precipitation is remarkably lower.
so for a weekly dose (accumulated dose) of 1,73ppm PO4 I would need at least 0,030ppm of Iron +micros (Iron as a proxy) @_Maq_ ?? Or this is a 0,030ppm ratio for Fe daily? (sorry If this is dumb question).
 
Marschner
hey @_Maq_ - am I seeing it right? Are you trying to apply terrestrial plants dosage routine to underwater plants? Or is it for emersed forms sprinkled occasionally with rain water infused with ferts? Do you keep them in mud or in the tank fully filled with water?

There are some reactive compounds highly dependant on alkalinity of environment, water/humidity at all etc (Fe is one of most reactive among them) and I'd personally rather avoid applying ratios suitable for terrestrial plants to the underwater ones - personally I think doses of Fe compared to the others are extremely low in the table you've attached above - in the highly humid environment (I mean water) Fe will quickly go bust - depending on acidity and other variables.

Of course there are different ways, experiences etc and many of us could argue if we need a PO4/Fe/N/K bombs etc. but personally for 1 mg (roughly) of Phosphorus I'd keep at least of 0.1 mg of Fe present and available for plants at all if possible.

Other micros like boron, nickel etc are another subject, they are generally almost always present in the soil and if this is not an intensive plant farming I'm not bothered at all - but they are generally present in most of commercially avialable ferts anyway.
 
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Or this is a 0,030ppm ratio for Fe daily? (sorry If this is dumb question).
It does not depend on time. Ratios are valid no matter what.
Are you trying to apply terrestrial plants dosage routine to underwater plants?
The difference is not as substantial as it seems. Even terrestrial plants uptake nutrients only dissolved in water. The rules of nutrients vs. water interactions are the same. And the water within water column is often better oxygenated than porewater in soils.
 
More & more, I've been pondering the influence of (a) temperature, and (b) temperature changes.
From November to February, the average temperature of my tanks (Portugals) is 19.0 °C. Now it's close to 25 °C, and "events" happen. I can see improved growth of some plants (Araceae!), but also blooms and thread algae, in some tanks, at irregular periods. Also, the same mineralization leads to significantly higher pH. (That one is particularly interesting, indeed.)
I assume that the microbial community balance definitely can't be the same in winter and in summer. It must have developed somehow, and imbalances occurred. In the end, these lead into irregularities in that part of my tanks' life which I can perceive (unlike "wars" between selected groups of bacteria).
I wonder if maintaining constant temperature during the whole year ought to be recommended?
 
More & more, I've been pondering the influence of (a) temperature, and (b) temperature changes.
From November to February, the average temperature of my tanks (Portugals) is 19.0 °C. Now it's close to 25 °C, and "events" happen. I can see improved growth of some plants (Araceae!), but also blooms and thread algae, in some tanks, at irregular periods. Also, the same mineralization leads to significantly higher pH. (That one is particularly interesting, indeed.)
I assume that the microbial community balance definitely can't be the same in winter and in summer. It must have developed somehow, and imbalances occurred. In the end, these lead into irregularities in that part of my tanks' life which I can perceive (unlike "wars" between selected groups of bacteria).
I wonder if maintaining constant temperature during the whole year ought to be recommended?

Given you dose nutrients on such a lean basis, do you alter them at all as the temperature increases?
 
Given you dose nutrients on such a lean basis, do you alter them at all as the temperature increases?
No, I don't, but:
I'm trying to manage pH through bicarbonates. During winter, I routinely have to add some of the minerals (calcium, mostly) in bicarbonate form to prevent pH falling too low. Now, I don't use any bicarbonates and pH in all four tanks is between 6 and 7. I've had to increase iron dosing.
Now, the question is whether this is due to higher pH - and thus higher loss of iron - or increased microbial population and their iron consumption.
 
No, I don't, but:
I'm trying to manage pH through bicarbonates. During winter, I routinely have to add some of the minerals (calcium, mostly) in bicarbonate form to prevent pH falling too low. Now, I don't use any bicarbonates and pH in all four tanks is between 6 and 7. I've had to increase iron dosing.
Now, the question is whether this is due to higher pH - and thus higher loss of iron - or increased microbial population and their iron consumption.

I was just wondering if the increase in temperature increases plant metabolism (which you’ve observed with increased growth rate) which then induces a slight deficiency if the very lean dosing regime isn’t increased to compensate, leading some release of organics from the leaves and a resulting foothold for algae?
 
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