I suppose the water is soft / the alkalinity is low in these tanks?
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Is Tom Barr's Approach Still The Go To Approach For Low Tech?
- Thread starter Harry Muscle
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I suppose the water is soft / the alkalinity is low in these tanks?
Here's a closeup of A.Pedicatella adjusting to a lot less light than its neighbours by staying very green...
Hi all,
You get it with variegated cultivars of Ivy (Hedera helix) as well, they go green ("produce more chlorophyll") in very low light conditions. You get it a lot in the winter when you keep them as houseplants.
cheers Darrel
That looks fairly conclusive.
You get it with variegated cultivars of Ivy (Hedera helix) as well, they go green ("produce more chlorophyll") in very low light conditions. You get it a lot in the winter when you keep them as houseplants.
cheers Darrel
John q
Member
Yes and yes.
Yes, the water usually had 0-1 dkh and 2-3 dgh, I often change the dgh to see the response from the plants, but dkh is always kept close to 0. Fe will be influenced if the dkh were to be high and may require changes. but, K can be kept within the same range.
Yes, that is right, I have to dose 0.8 ppm Fe weekly in my aquariums with 12 dKH. I also bring down pH with a single dose of CO2 every morning to keep it in the solution a little bit longer. And I think that because of the amount of iron, and the phosphate precipitation, I also have to dose lots of phosphate (2x 3 ppm/week). With significantly less PO4, I get GSA.
I dosed KNO3 (10-20 ppm/week) and KH2PO4 in my first planted tank. Potassium from the KNO3 should be enough in theory, and most of the online sources say that if you dose KNO3, you don't need extra potassium. However, I ran into a serious potassium deficiency with my Hygrophila and Microsorium plants, and once I started dosing extra K at 20 ppm/week, they recovered. According to our National Public Health Center, sodium concentration in the water in my town contains up to 29 ppm sodium (median 15). My guess is, that since sodium and potassium can use the same transporters (proteins in the cell membranes that facilitate ion transports across the cell membranes that are otherwise not permeable to ions) across the cell membranes, there might be a competition between these two ions. The sodium might be outcompeted with the extra potassium. It is a speculation on my part, but it seems plausible, fits my experience, and I can even find some supporting references (1, 2, 3).
My point is, that water parameters affect the dosing, so the same lean levels may not be enough in all conditions. I also suspect that chloride and maybe bicarbonate in water could affect the uptake of other negative ions, nitrate, and/or phosphate. Tom Barr's method might take care of these competitions by providing an overload of every nutrient.
John q
Member
True lean dosing will not work in anything other than soft water.
I think that's why ei gained traction and is still the go to formula for many, it doesn't discriminate. Lol.
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Hi all,
I think that where the <"Duckweed Index">* has an advantage <"over all other methods"> is that you can use it for both <"lean dosing and triffid">.
*Although I may not be an entirely <"unbiased commentator">.
cheers Darrel
I'm obviously not an EI user, but I think that is the <"advantage of both Estimative and Duckweed Indices">, you don't need to worry about <"ratios or trying to measure"> the amount of nutrients in the water column.
I think that where the <"Duckweed Index">* has an advantage <"over all other methods"> is that you can use it for both <"lean dosing and triffid">.
*Although I may not be an entirely <"unbiased commentator">.
cheers Darrel
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I believe you are dosing the following? great job on your thread, I always appreciate people who like to do experiments. I would try to increase the Mn from 0.05 to 0.1 ppm and you can also increase the Cu a little if you like.
Fe-DTPA: 0.2 ppm Fe
Borax: 0.03 ppm B
Zinc sulfate: 0.02 ppm Zn
Manganese sulfate: 0.05 ppm Mn
Na2MoO4: 0.0015 ppm Mo
CuSO4: 0.0015 ppm Cu
Potassium and Sodium Competition is well documented on terrestrial plants, not just Potassium and Sodium but several other nutrients as well. but the answer isn't simple as adding more K to fix the problem, you may very well be creating other balance or imbalance by doing that, particularly Ca and Mg is being influenced here. the deficiency chart most people use are taken from terrestrial plant and K deficiency could be replicated by many other nutrient deficiencies, in other word, you can have pin holes on the leaves due to simple as one of the Micro. we are relying on terrestrial plant data vs Aquatic plant Data to determine this, am not saying the data cannot be used but we should always keep in mind that nutrients behave differently in the solution/Water vs in the soil and same is true for plants grown under the water vs grown outside the water.
I have seen people posting about having Potassium deficiency in these same plants "Hygrophila and Microsorium" despite having 50+ potassium level in their tanks, sometime the solution turn out to be simple as chaining the Micros brand to something better. and the problem was never related to K at all, I believe you are currently doing some experiments, which is good and am proud of that. I also believe that most people use terrestrial plants deficiency chart to determine nutrients deficiencies in aquatic plant, I believe this is not 100% accurate. Ca, Mg, K ratio or imbalance play rather more important role, having them in different set of ratios create Mg deficiency, Ca deficiency, K deficiency and vice versa or the other way around. In your case of adding additional K fixing things, it involves several factors, including the one you mentioned but that's not a full story and it certainly doesn't tell us the uptake of K. You believe that excess Na+ causing issues with K+, so I assume you admit that these interactions are real? EI ignore these factors and was never designed to consider them important, it even advocate that these balances, imbalances or interactions don't exist.
according to this site: "For decades an ample amount of work has been done on the substitution of K+ by Na+ in plant nutrition. In this regard, Na+ has the potential to replace K+ for some of its functions. In some plants, supplementation of Na+ in reduced amounts can eliminate K+ deficiency symptoms under limited K+ supply."
you are likely to experience this more often than the Na+ and K issue. for example: Fe and P issue is very common, some people ignore the Mn and this is also underlying cause of what people call Fe deficiency, but truly its Mn deficiency. when plant look Fe deficient, always look into Mg, Mn and Fe first.
while water parameters affect the dosing, the solution isn't simple as providing an overload of everything in excess, then you may correct one thing but cause another imbalance. "EI ignore these factors and was never designed to consider them important, it even advocate that these balances, imbalances or interactions don't exist." and I have never seen Mr. Barr made any claim that EI was designed to take care of these competitions or imbalances, never. the most common issues in hard water is almost always Fe related followed by Mn and Mg.
as always, I find this information to be misleading and Inaccurate.
if this was the case, I have hydroponic solution at my disposal which is several times concentrated than the EI and it should also take care of that imbalances or interaction issues listed above.
John q
Member
Why? Have you had success with lean dosing hard water.
MichaelJ
Member
Higher dGH is largely not a problem unless the calcium level is very high as it may inhibit uptake of other elements. It's definitely beneficial to have low dKH/Alkalinity - in other words carbonates - as you wont have to worry about pH being too high and limit bioavailability of say Fe and Mn. I would suggest that in alkaline water you just have to be mindful of the chelate of choice and possibly dose more Fe and Mn. Otherwise, I see no reason why you can't dose lean levels of N P and K in harder water and still make it work. My shrimp tank is probably considered moderately hard in terms of minerals with a dGH of 4.5 and plants seems to be doing just fine with being very leanly dosed.
Cheers,
Michael
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I have gradually changed the dosing since that post and I am at these weekly values now:
0.8 ppm Fe
0.07 ppm B
0.02 ppm Zn
0.4 ppm Mn
0.0015 ppm Mo
0.0015 ppm Cu
So I increased mainly the iron and manganese and have nicer frogbits now. I am more careful with Cu though, but maybe I could try that too. I am playing with magnesium as well.
I don't want to suggest that potassium and sodium interaction is merely a competition and one could solve the problems related to high sodium content in water in any circumstances simply by overloading the potassium. Yes, there could be other explanations for my observation. But if I have potassium deficiency-like symptoms (pin holes in leaves and deteriorating plants) and they recover after potassium supplementation, I lean toward accepting that there might have been a potassium deficiency despite the theoretically good potassium levels. The simplest explanation for me could be the interplay with the relatively high sodium. I do not say that it fully explains it, but it is a possibility.
I am sure that there are interactions. For one, there is the interplay between the KH and the iron availability. We could say, that there is a "balance", if the water has a higher KH, it might need more iron to balance that out. But instead of speaking of vague "balance" effects, I like the more specific and mechanistic explanations. One such explanation would be that iron precipitates out as phosphate or other salts if the pH is high because of bicarbonate. The simple "Fe precipitates out" mechanistic description might not be the full depth of problems when the KH is high, but addressing a single aspect of it (the iron availability) helps already for sure. On the other hand, the term "imbalance" in the same system might fully incorporate all the dimensions of the high-KH problem, but it is less helpful if we try to address it and intervene.
So while I accept that the potassium effects are much more complicated, I don't think we should rule out the usefulness of the sodium-potassium competition as a possible point of action. It is something worth considering.
I think we need to separate the observations from the interpretations. It seems to me that Tom Barr's approach gives good results regarding plant growth and health in many aquarium systems/conditions. He and many others have had good results with it. The interpretations are limited by our knowledge and could change with time, that is the nature of biology. What matters is the results and the reproducibility of the results. What he believes, and how he explains his results does not change the effectiveness of his approach. I have not seen such claims that EI was designed to take care of these competitions either, I just think that it could be one effect of it.
I don't like the interaction chart though. It is probably overly simplified to fit a lot of information on a single chart, and at the same time, it is too complicated. The only conclusion from this chart for me would be that almost everything is connected to almost everything, which does not help a lot. It does not differentiate the nature and the significance of the interactions. For example, I would think that the interaction between iron and phosphate has an impact more often in a typical aquarium than the interaction between phosphate and calcium. Still, they are indicated the same. Based on this graph, I could also conclude that if I increase the dosing of one of the nutrients for some reason, I would have to increase all the others as well to keep everything in balance. And that might lead to a dosing similar to Tom Barr's approach with all nutrients overloaded.
The fact that there are so many unknowns and things to be discovered keeps this hobby interesting for me. No running experiments at this time though, but have plans to run a few CO2-related ones once I find some spare time for them.
ElleDee
Member
(I apologize in advance for going off on this one point when you made some other great points.)
A couple years ago I tried to track down the original source for the chart and it seemed to come from a talk at a pomology conference in the 50s. In the process I came across a lot of other nutrient interaction research from that time period and the results are not consistent. I suspect this was a hot area of research during the day, but didn't pan out in the long run.
That's not to say the nutrient interactions don't exist. They do, but it's complicated and hard to generalize. Here's a contemporary review for the interested:
Effects of Nutrient Antagonism and Synergism on Yield and Fertilizer Use Efficiency
Of course it's focused on field crops, but what do you expect. (I read this article when I fell down the rabbit hole on this, but don't quiz me on it today, thank you. 😅)
I don't know why Mulder's chart is ascribed to in certain niche fields including our hobby, and I don't blame anyone for citing it because it is often presented as settled scientific fact rather than some midcentury musings of an obscure fruit tree guy. But I think it would be beneficial to the hobby if we moved on from that particular graphic.
I would go as far as to say Mulder's chart is not supported by research and we should toss it.
A couple years ago I tried to track down the original source for the chart and it seemed to come from a talk at a pomology conference in the 50s. In the process I came across a lot of other nutrient interaction research from that time period and the results are not consistent. I suspect this was a hot area of research during the day, but didn't pan out in the long run.
That's not to say the nutrient interactions don't exist. They do, but it's complicated and hard to generalize. Here's a contemporary review for the interested:
Effects of Nutrient Antagonism and Synergism on Yield and Fertilizer Use Efficiency
Of course it's focused on field crops, but what do you expect. (I read this article when I fell down the rabbit hole on this, but don't quiz me on it today, thank you. 😅)
I don't know why Mulder's chart is ascribed to in certain niche fields including our hobby, and I don't blame anyone for citing it because it is often presented as settled scientific fact rather than some midcentury musings of an obscure fruit tree guy. But I think it would be beneficial to the hobby if we moved on from that particular graphic.
MichaelJ
Member
I am not familiar with the Mulder's chart (isn't that the guy from The X Files btw?) .... I do see the chart widely quotes when I do a search... a lot of contemporary agriculture related sites refer to it - including US state level agriculture institutions. I don't know the level of acceptance of the science behind it. Perhaps @Happi can shed some light on it. There is zero doubt in my mind that many of the chemicals we add to our tanks interacts directly or indirectly and vary among elements, but to what extent and how important it is as it pertains to our plants health I do not know.
Oh, you mean like the obscure theories of that obscure patent clerk that worked for the Swiss Federal Patent Office in Bern between 1902-1909
Cheers,
Michael
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ElleDee
Member
Yes, lots and lots of sources publish the chart, but they are doing it uncritically because they have seen it somewhere else and didn't look into it. This is a pretty normal thing to do. The only reason I looked into it is because I had literally never heard of it before and I have a graduate degree in horticulture. I am not a plant nutrition expert, so I figured I missed it and when I dug into it I wasn't seeing citations from this institutions and journals I expected it from and I couldn't find the original source.
I see that since I looked into it myself, someone else had the same question I did last year and looked into it even further here. I don't know anything about the person who wrote this, but I could have written it up until they actually found the original paper! I found the withdrawn abstract on the BYU website and gave up. I suggest giving it a read! The author doesn't entirely discredit Mulder and gives a lot of useful context from the original source, but regardless it's not really an actionable chart.
I think the review I posted is a better picture of the state of the science, at least it was the last time I looked into it.
I shouldn't have insulted fruit tree guys anyway - I did my graduate research at a station with research orchards and it's serious business and real science. Mulder probably had a fine career - I came across enough contemporaneous references to him to suggest he was, you know, a working academic, but he didn't make it into of any of my textbooks in the 2010s. He's not in Marschner either.Oh, you mean like the obscure theories of that obscure patent clerk that worked for the Swiss Federal Patent Office in Bern between 1902-1909
Cheers,
Michael
Thanks for the link, very interesting reading! This is quite usual with science, sometimes things get once into the textbooks, get widely accepted, and are hardly reviewed thereafter for decades, even if the information gets outdated in the scientific literature. It is just impossible sometimes to go after every bit of information.
On a side note, this Mulder story also shows how important is the way the data are presented. It must have been rare that people used such diagrams (can we call this a chord diagram?) at the time, and here we are 70 years later looking at the same chart.
aquanoobie
Member
The numerous ion antagonism and synergism interaction charts are well accepted phenomenon amongst animals and plants. It's not like the moon landing, you know.
Bradders
Member
What moon landing?
John q
Member
