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Amazon water types vs. "natural fertilizer" levels

MichaelJ

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Minnesota, USA
Hello, I thought this was interesting: Chemistry of different Amazonian water types. Now, the paper is not specifically about aquatic plants in the Amazonas, but I thought it was interesting how low the water column levels of essentially every mineral are in the rivers they sampled from.

I personally have no doubt that my EI level dosing is working for my low-tech tanks... as I have zero algae to speak of and excellent plant health across the board - slow, but steady and healthy growth. It is however a very stark contrast to what seems to be the case in nature. Why do we keep our fertilizer levels so high in our tanks - in many cases orders of magnitude higher - when the rivers where a lot of our plants come from contains pretty much nothing of anything we consider important?

Soil levels perhaps are providing all the nutrients the plants needs?

Thoughts?

Cheers,
Michael
 
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Good question. Some areas are without a doubt very densely "planted", but I suppose it is very hard to compare.

I would think lush/dense underwater plant growth is an exception in most cases? Especially compared to what we have in our tanks.

A lot of habitats are rather sparse in plant life, and blackwater habitats are mostly empty which the amazon region has a lot of.
Soil levels perhaps are providing all the nutrients the plants needs?
Soil would provide a lot of nutrients for sure. Most of the plants we keep are not true aquatics either, they're bog/marginal plants
 
I would think lush/dense underwater plant growth is an exception in most cases? Especially compared to what we have in our tanks.
That is true - very hard to find footage / pictures of natural habitats with lots of vegetation (except for underwater footage of flooded terrestrial plants during the rain season).

What I especially find intriguing here are the ratios... say for instance 0.04 ppm of NO3 for Tapajós... with EI we routinely keep our NO3 levels at 20-30 ppm. that's 500-750 times as much :) ...that might be an extreme. Some of the locales mentioned in the thread that @Happi posted above also list some of plants growing on those locales, such as several species of cryptocoryne, blyxa aubertii, hydrilla verticillata, barclaya motleyi, potamogeton wrightii in Tasek Bera, Malaysian Peninsula, where NO3 levels allegedly is in the 0.1 ppm range.

And blackwater habitats are mostly empty which the amazon region has a lot of.
Very true.
Soil would provide a lot of nutrients for sure. Most of the plants we keep are not true aquatics either, they're bog/marginal plants
It would be interesting to see a soil analysis from some of these areas.

Anyway, very fascinating.

Cheers,
Michael
 
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@MichaelJ

We have to consider the NH4 as well in those water, The low amount of NO3 doesn't matter because plants are mainly using the NH4 constantly in those waters.

Some will argue that it's the soil that is providing most the nutrients but then you should ask them why dose 30 ppm NO3 in the water then?
 
as I have zero algae to speak of and excellent plant health across the board

This is the key point. You will very rarely see “zero algae” and “excellent plant health” in a natural environment.

You will generally see extensive algae, and a mixture of healthy and completely ragged/deficient/damaged plant growth. That’s a natural environment, but not what we necessarily want to see in our glass boxes, so we employ a number of techniques, including dosing sufficient nutrients, to prevent that happening.
 
@MichaelJ

We have to consider the NH4 as well in those water, The low amount of NO3 doesn't matter because plants are mainly using the NH4 constantly in those waters.
Yes, I thought about that, and that makes total sense, but then again, it's the same story for all the other major nutrients we are dosing in abundance - such as P, K and Mg.

Some will argue that it's the soil that is providing most the nutrients but then you should ask them why dose 30 ppm NO3 in the water then?
I would love to see a reference to a soil analysis.

Cheers,
Michael
 
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Some will argue that it's the soil that is providing most the nutrients but then you should ask them why dose 30 ppm NO3 in the water then?
The soil in our tanks is very different to soil in nature.

There are finite amounts of nutrient stores in aquarium soil, when used up water column dosing is needed. In nature the nutrients in the soil are constantly replaced.
 
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You will generally see extensive algae, and a mixture of healthy and completely ragged/deficient/damaged plant growth. That’s a natural environment, but not what we necessarily want to see in our glass boxes, so we employ a number of techniques, including dosing sufficient nutrients, to prevent that happening.
Hi @Wookii Good point and true judging from pictures and footage from these habitats. I live on a comparatively healthy lake here in Minnesota and the vegetation does look somewhat scrawny with algae growth etc. plants appear healthy enough to get by but nothing that compares to what we have in our tanks when they are well-fed and well maintained.

Cheers,
Michael
 
Hi all,
Are those streams as heavily planted as a typical heavily planted tank?
except for underwater footage of flooded terrestrial plants during the rain season
They are all "planted", just many of the aquatic plants are trees.

<"White water rivers"> that flow from the Andes have a sediment load (and some bases), and they don't have any submerged vegetation (but may <"have Pistia etc floating">), they are flanked by <"Varzea meadows and forests"> that flood as the water level rises. Clear water rivers from the Guiana shield have <"submerged aquatic plants"> and black water streams in the Rio Negro catchment have the "flooded forest". They, the trees and herbs of the flooded forest, aren't really terrestrial, you could argue that are just as much aquatic plants as Cryptocoryne spp. etc.

cheers Darrel
 
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37052688_10155852843328666_6927140996945805312_o.jpg
 
Interesting. Probably slightly off-topic, but is there any explanation for the high carbon dioxide levels in Biotope no. 1-3? Could it possibly be from respiration of the submerged rootzones of trees etc whose CO2 consuming parts are emerged?

Could also be the result of biological processes breaking down huge amounts of organic matter from run off during the rainy season and general leaf fall into the rivers assuming most of the quoted rivers are in heavily forested areas.

I believe it’s common for natural bodies of water to have much higher CO2 levels than we would typically see in a low tech aquarium for example.
 
I think we should be mainly focused on the water parameter of those rivers rather than jumping into the soil at this point. because there is no data posted about the soil so we would be just guessing at this point, but we have a data about the water parameters which should be our main discussion.

if you were to dose say 0.32 ppm NH4 daily and match the other nutrients such as PO4 at 0.12 and dose daily, you are actually not far away from how ADA, Tropica dose their tanks. I also dose in a similar manner where Ca, Mg, S, Cl, Fe are also very low. for example just look at my Marchner ratio experiments.

these data's can be replicated and be used in our aquarium if one want to really try it.
 
because there is no data posted about the soil so we would be just guessing at this point
these data's can be replicated and be used in our aquarium if one want to really try it.

Indeed they can, and many people do lean dose with great results, but as you point out the soil at this point is an unknown variable, but very likely an important one in terms of nutrition.

I would like to start reducing my nutrients to try and tease more colour out of my plants, I will be doing this slowly but likely will be still dumping in much more ferts than needed.

EI works, it is easier for people as it means they don't have to worry about making sure they have 0.32ppm of this and 0.1ppm of that and can concentrate energy on harder aspects. I do think once you have a handle on everything else there is no harm in messy around with ferts though.
 
Hi all,
It would be interesting to see a soil analysis from some of these areas.
In the "black-water" forests the soil is a very thin organic layer over silica sand, I'd guess that most nutrients would be in trace amounts. There would be a lot more nutrients in the varzea sediments, but I don't know the exact amount.

The <"turned up to eleven"> thread about <"Overwintering Ludwigia sedioides"> suggests that nutrient levels are reasonably high in the varzea zone. This is what RBG Kew says about growing the <"Giant Amazon Waterlily (Victoria amazonica)">.
........ Around January or February, the brown to black, pea-sized seeds of the giant waterlily are placed under grow lamps in water kept at 28–30°c in our Tropical Nursery. New seedlings develop over the course of a few weeks with leaves roughly the size of a CD. Around mid-March, they are planted in loamy soil in a large pot and placed in the middle of the pond in our Waterlily House which is kept at 28°c.

The seedlings are fertilised weekly with a mixture of loam and organic fertilisers that are inserted into the soil.........

cheers Darrel
 
I think we should be mainly focused on the water parameter of those rivers rather than jumping into the soil at this point. because there is no data posted about the soil so we would be just guessing at this point, but we have a data about the water parameters which should be our main discussion.

if you were to dose say 0.32 ppm NH4 daily and match the other nutrients such as PO4 at 0.12 and dose daily, you are actually not far away from how ADA, Tropica dose their tanks. I also dose in a similar manner where Ca, Mg, S, Cl, Fe are also very low. for example just look at my Marchner ratio experiments.

these data's can be replicated and be used in our aquarium if one want to really try it.

I don’t think you can exclude the soil, or indeed anything else - those natural environments couldn’t be farther removed from our tanks trying to translate one to the other is impossible. Plant density, light intensity, water clarity and chemical composition will be wildly different.

Also bear in mind, those nutrient figures are long run accumulation numbers, not a daily addition. Assuming you do a 50% water change each week, you may need to dose a fair bit less than that daily depending on plant uptake.
 
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