Maq's Substrate Experiment

[Little]

Hi Maq. Happy new year. Thanks for your research.

Based on your early indications…
Would an aqua soil tank benefit from a little additional iron (chelate?) to help it start well?

My tank has very hard water*, 400tds, 7.7-7.2ph, 5kh and is in a 10 week dark start so I have no duckweed / frogbit index yet but easy access to the soil / substrate.

*tap water from far SE England, constant limescale building on taps etc…

 

[_Maq_]

I can reply only in general terms. This is my first experience with aquasoil.
So, if you're cursed with hard water, you have basically two possibilities:
(1) Dosing iron in the water column. Advanced chelates are probably necessary.
(2) Dosing iron in the substrate. Iron in the substrate is subject to bio-chemical cycling. Iron tends to precipitate but plants' roots and microbes are very ingenious in finding their ways to "inaccessible" iron. Therefore, I think it makes little sense to inject chelates into the substrate. They would be transformed in other forms of iron quickly and completely. However, any substance containing iron will get transformed within the substrate in time. So, with adding iron nails or powdered ferric oxide to the substrate, you cannot expect instant results, but given time, it will work well.

 

[Little]

Thanks Maq. Much appreciated.

 

[erwin123]

Only in tank D, Lugwigias seem to be in full health, while (interestingly) in tank C, the iron deficit looks quite hard (but probably overcome, already).
I really would like to believe that the microbial inoculation in tank D helped the plants to cope with iron deficiency better than in other tanks. But of course, we cannot consider these observations as a proof, just a suggestion - "perhaps".
I've been intrigued by signs of iron deficiency in tank C. Aquasoil is supposed to be a rich source of all nutrients (and measuring ammonia/um seems to confirm that). How come iron deficiency, then? What if phosphates leached from aquasoil prevented some plants from acquiring iron? Remember, Ludwigia cuttings were rootless, depending on nutrients in the water column.

Actually the L. Pantanal /Meta is tank C looks to be the best condition.
All the other tanks, the Pantanal/Meta leaves seems to be experiencing 'leaf droop' especially on the lower leaves?

 

[dw1305]

Hi all,

Iron deficiency seems to persist, so today I've added 16.8 µg/L iron (as ferric chloride).
Interestingly (and rather surprisingly), no trace of algae, yet.

I wonder if those <"two factors are related">?

cheers Darrel

 

[dw1305]

Hi all,

Dosing iron in the water column. Advanced chelates are probably necessary.

Personally I'd go down the FeEDDHA and <"pink tinge route">.

My tank has very hard water*, 400tds, 7.7-7.2ph, 5kh and is in a 10 week dark start so I have no duckweed / frogbit index yet but easy access to the soil / substrate.

*tap water from far SE England, constant limescale building on taps etc…

We all tend to have the <"same water parameters in the SE of UK"> (away from the Weald).

cheers Darrel

 

[Little]

We all tend to have the <"same water parameters in the SE of UK"> (away from the Weald).

I’m in Ashford, I use softened water for my espresso machine and kettle and rainwater for the allotment but really hoped to just use tap for the aquarium.

 

[_Maq_]

I use softened water for my espresso machine and kettle

I'm not in coffee but I can swear tea is miles better made of RO water!

 

[dw1305]

Hi all,

and rainwater for the allotment

I'm a rainwater user. If I didn't have access to rainwater? I would use our tap water <"If it's yellow, let it mellow and RO is the devil">. We have a water softener, but it gets through <"a lot of salt">.

I’m in Ashford

You could potentially get water that varies throughout the year, dependent on source (chalk aquifer or reservoir) <"Reservoir levels in our region"> , but I'd just go with "very hard" <"Some handy facts about water">.

Only about 7% of the water we supply comes from reservoirs – follow the link to find out more about where our water comes from.

cheers Darrel

 

[_Maq_]

Actually the L. Pantanal /Meta is tank C looks to be the best condition.

Noooo. Look better. They lag behind in growth, too. And if a few leaves display intensely red coloration, it's largely because of lack of chlorophyll = iron deficiency.

 

[Little]

I'm not in coffee but I can swear tea is miles better made of RO water!

Agreed! Tea and coffee are both hugely improved by good water chemistry. The coffee industry has people also making a killing from expensive / high markup remineralising packs

E.g Third Wave Water 2L Box

 

[dw1305]

Hi all,

The coffee industry has people also making a killing from expensive / high markup remineralising packs

This is a new one for me, but I sense <"another competitor"> in the <"World's Most Expensive Water Contest">.

....... One of our go-to ways of achieving consistent and balanced water chemistry is Third Wave Water mineral sachets. Based on the <"SCA water profile">, Third Wave Water is easy to use and allows you to highlight flavours, reduce the bitterness and achieve optimal extraction rates in a few easy steps.

The flavour of your brew is not only determined by the quality of your beans, but also the minerals present in water. The lower the concentration the softer the water, and the higher the minerals, the harder the water. To get the perfect PH balance for brewing delicious coffee add 1 mineral sachet to 2L of distilled water........

Do we have an ingredients list? I'm going to guess not.

cheers Darrel

 

[JoshP12]

Maybe this is why they recommend the Bacter 100 in the aquasoil?

I think your point on PO4 leaching out and preventing available iron is valid. The bacteria no doubt would help make it available at rhizosphere … especially early on and/or to compensate for what cannot be attained in the column. I think this goes for all micros … we’re just seeing it with iron because we need more iron than the rest. I wouldn’t be surprised if we went back in time and dosed more iron in the aquasoil tank from the beginning to compensate for what we know now, you would see Mn deficiency. And you could probably isolate all the way down.

I think it further solidifies the idea why hard water needs more N/P in it. For the same reason. No one is denying the micronutrients are in aquasoil - but why can’t the plant just take it out? In the same way when people rely exclusively on water column feeding — well the “nutrients” are there … why can’t the plant just take them out? Ideology to add more comes in search of the balance.

Your point on grain size and root formation (unique to species) is also going to play a factor in the influence that the impact root feeding will have on those species given a particular substrate - feasible that the reliability of root feeding varies with substrate size, unique to species.

I think it just goes to show that what the hobby needs is a flow chart that points to highest probably of success - which we don’t have yet - given a series of fixed decision (such as source water).


Really loving the experiment!

 

[ElleDee]

Ahh, this is all reminding me how annoyed I am about how little information is available about what is actually in aquasoil.

Also ADA has so many little additives you are meant to layer under it, including iron tabs, and I've seen it all dismissed as overpriced marketing gimmicks, but I think it's difficult to assess when we don't know what it all is specifically. I mean, the magic hand of marketing is definitely at work, but that doesn't mean there's nothing useful in there. An iron deficiency right out of the gate certainly leaves something to be desired.

In addition to liming the soil in my dirted tanks I also added some of my native iron-rich clay and I suspect it has saved the tank from serious iron issues as the kh has crept up.

 

[dw1305]

Hi all,

Ahh, this is all reminding me how annoyed I am about how little information is available about what is actually in aquasoil. Also ADA has so many little additives you are meant to layer under it, including iron tabs, and I've seen it all dismissed as overpriced marketing gimmicks, but I think it's difficult to assess when we don't know what it all is specifically.

That is the problem, the <"unknown unknowns">. Personally I'm willing to trade any short term enhanced growth for longer term stability, so I don't really <"see a need"> for aquasoil type substrates. I know @_Maq_'s thought process goes along the same lines <"Cloudy Water Hazy Water and Algae!">.

I mean, the magic hand of marketing is definitely at work, but that doesn't mean there's nothing useful in there. An iron deficiency right out of the gate certainly leaves something to be desired.

I think we can make some guesses <"Hobby laterite balls? Any reviews?"> & <"Substrate rinsing">.

Substrate
In nutrient terms rooted plants have access to the substrate, and that is a world of <"unknown unknowns">, with a huge number of <"potential variables">. Nutrients that aren't available in the water column <"may be plant available"> within the substrate, but not to floating plants and epiphytes (or <"algae">).

What the "Duckweed Index" allows us to do is side-step the thorny, multifactorial question of what happens in the substrate (should you have one) and just concentrate on the water column, and whether all the nutrients are plant available within it. Bryophytes (mosses and liverworts), plants grown as epiphytes (like <"most Aroid and ferns">) and floating plants are all reliant on nutrients in the water column, but all plants <"can take up ions via their foliage">.

Personally I'm <"going to watch the plants"> and add an iron chelate if I need to.

cheers Darrel

 

[_Maq_]

how annoyed I am about how little information is available about what is actually in aquasoil

My way of studying these problems went a different way. I've read some textbooks on soils. They told me what matters and why. Only then I've immersed into commercial "aquasoils" and what info the vendors were willing to share.
It should not come as a surprise that every useful component of a soil is cheap. We're not after precious ingredients. Silica sands of various grain sizes, clays, iron compounds, decomposing organic matter, humic substances and peat... that's about all. Now the question about suitability for aquarium is mostly about texture. Not to make water permanently cloudy, not to hinder diffusion by a substrate way too compact, and also not to infest the water with too much organic pollution or mineral nutrients.
The problem of texture is neatly solved by granulation, but the other problems are not.
I have never tried most of the commercial substrates because I consider them overpriced. The potential benefits - if any - seem too low to me to make the price acceptable. Besides, I think some aspects of this topic are perceived in a wrong way. Namely (1) a reserve of nutrients, which is often harmful, and (2) an organic content, which is unsuitable.
Some good features of aquarium substrate cannot be delivered in an instant form; or, I'm not aware of any product fulfilling key criteria. Dead organic matter needs to be thoroughly decomposed to bring the right benefits. Such a matter develops in the substrate after certain time, and it's the result of microbial decomposition in situ. In actuality, it's a blend of living microbes, decaying organic matter, and polysaccharides created and permanently upgraded by the microbes (biofilms). This is the environment with excellent adsorption abilities and able to host full cycling of all elements. I don't believe anyone has succeeded to create it artificially and deliver in "plug & play" form.
My choice is silica sand (preferably of not uniform grain size) with some additives in modest amounts: powdered ferric oxide, cleaned and powdered clay, and a bit of peat, maybe. This is no nutrients reserve (with the exception of iron, partly), but a blend which I believe supports development of the substrate into a matured one, mostly thanks to their adsorption properties. I believe these additives help, because it's in line with what I've read in textbooks, but I know from my practice that even without these additives, plain silica sand develops in time (about a year) in an excellent substrate.

 

[ElleDee]

I understand that there's nothing magic in soils, but my point is that the way aquasoils are packaged are way out of line with other bagged substrates are sold, at least in the US. I have droned on about US fertilizer labeling regulations here before, and while I don't know what the relevant rules are here, the fact is that I can pick up a bag of potting soil at a big box store and it says right on it what the constituent parts are, the guaranteed analysis for NPK at minimum, usually with some notes on the form of nitrogen, and the source of any nutrients, whether that be the specific salts or bone meal or whatever. Not providing that information feels outrageous to me, like selling processed food without any nutritional or ingredient information. Maybe this is a very American perspective.

I have never tried most of the commercial substrates because I consider them overpriced. The potential benefits - if any - seem too low to me to make the price acceptable. Besides, I think some aspects of this topic are perceived in a wrong way. Namely (1) a reserve of nutrients, which is often harmful, and (2) an organic content, which is unsuitable.
Some good features of aquarium substrate cannot be delivered in an instant form; or, I'm not aware of any product fulfilling key criteria. Dead organic matter needs to be thoroughly decomposed to bring the right benefits. Such a matter develops in the substrate after certain time, and it's the result of microbial decomposition in situ. In actuality, it's a blend of living microbes, decaying organic matter, and polysaccharides created and permanently upgraded by the microbes (biofilms). This is the environment with excellent adsorption abilities and able to host full cycling of all elements. I don't believe anyone has succeeded to create it artificially and deliver in "plug & play" form.

I hear you about aquasoil not being the best value proposition. But when you say a reserve of nutrients that are often harmful, what do you mean specifically? The ammonia spike associated with Amazonia? And what do you mean about "unsuitable" organic matter? Again, it would inform the discussion if we actually knew how much organic matter is in aquasoil and of what nature. I am unclear how much of the nutrient content (whatever it is) is intrinsic to the raw soil being used and how much is the result of additives.

My choice is silica sand (preferably of not uniform grain size) with some additives in modest amounts: powdered ferric oxide, cleaned and powdered clay, and a bit of peat, maybe. This is no nutrients reserve (with the exception of iron, partly), but a blend which I believe supports development of the substrate into a matured one, mostly thanks to their adsorption properties. I believe these additives help, because it's in line with what I've read in textbooks, but I know from my practice that even without these additives, plain silica sand develops in time (about a year) in an excellent substrate.

I'm seeing a lot of parallels to the ADA base layer additives here! I don't mean that as an insult at all, but there is a similar thought line for sure.

Also, while I appreciate that substrates will develop on their own over time, the beginning of a tank is the most difficult time for people and I think there's value in any product or technique that can help you get through the first weeks as smoothly as possible.

 

[erwin123]

Also, while I appreciate that substrates will develop on their own over time, the beginning of a tank is the most difficult time for people and I think there's value in any product or technique that can help you get through the first weeks as smoothly as possible.

I feel that the 2hr aquarist/Dennis Wong recipe which involves a rich substrate is a good way to planted tank success.

At least there is a comprehensive "recipe" on the website which beginners can follow and achieve success. My journal has plenty of photos of algae infested plants (see above) when I started up my 90P but a few months later, the plants became nearly algae free. The only thing I needed was stability. Not the Seachem product but actual stability in terms of CO2 and nutrient delivery, and water parameters. So instead of plants expending energy trying to adapt to changing conditions, they can devote their energy to growing new and healthy leaves.

I frankly did not see any Ammonia Spike with ADA Amazonia II. I presume the difference between Amazonia I and Amazonia II is that for II, the soil itself contains less Ammonia and instead they give you root tabs which probably contain ammoniacal nitrogen - so if you don't add those root tabs all at once, you won't get an ammonia spike

 

[dw1305]

Hi all,

I can pick up a bag of potting soil at a big box store and it says right on it what the constituent parts are, the guaranteed analysis for NPK at minimum, usually with some notes on the form of nitrogen, and the source of any nutrients, whether that be the specific salts or bone meal or whatever.

I agree. All fertilisers have to have a nutrient analysis, and that would be included on bags of <"John Innes (JI) mix"> and peat or coir based potting media etc., but after that it is a bit of a mess at the moment ,<"post BREXIT">.

There are British Standard for Potting Composts, they are more complicated than they used to be <"Growing Media and Special Requirement Guidance for Exports to the EU - UK Plant Health Information Portal"> because of the issue of any green-waste component.

But when you say a reserve of nutrients that are often harmful, what do you mean specifically? The ammonia spike associated with Amazonia? And what do you mean about "unsuitable" organic matter? Again, it would inform the discussion if we actually knew how much organic matter is in aquasoil and of what nature. I am unclear how much of the nutrient content (whatever it is) is intrinsic to the raw soil being used and how much is the result of additives.

Personally, for aquarium use, I keep well away from any potting compost and particularly any containing either green-waste compost (that is my "unsuitable organic matter") or added nutrients. Green-waste based compost has its own BSI <"PAS100">.

........ Samples are rigorously examined to ensure there are no constituents that could affect the quality of the compost and be harmful to people and the environment. PAS100 testing involves various stages: tests for heavy metals, harmful bacterial and contaminants for example E. coli. It also goes through a plant grow response test to ensure it is not contaminated with any pesticide or herbicides– this involves a sample of our compost being used to grow tomatoes from seed; this test examines seed germination, and any germinated seedlings are then checked for any abnormalities at 14 and 28 days.....

It is everyone to their own, but if I was going <"down the soil route">? I'd mineralize a relatively <"small amount of garden soil">.

cheers Darrel

 

[_Maq_]

what the constituent parts are, the guaranteed analysis for NPK at minimum, usually with some notes on the form of nitrogen, and the source of any nutrients, whether that be the specific salts or bone meal or whatever. Not providing that information feels outrageous to me, like selling processed food without any nutritional or ingredient information. Maybe this is a very American perspective.

If American by origin, it has definitely spread (Western) worldwide. But aquarium hobby seems to be somehow specific. There are so many products on which the manufacturers provide deliberately unclear, confused information. We are almost accustomed to false information and myths.

But when you say a reserve of nutrients that are often harmful, what do you mean specifically?

(1) I'm a hardcore fan of relative nutrient ratios. If the nutrient availability is unbalanced, ramifications are worse than when all nutrients are in an evenly short supply. This is not commonly accepted but my experience with lean regime is extensive and clearly supports the importance of relative ratios.
(2) I very much believe that large supply of nutrients is not what plants in newly established tanks need. [Current experiment to which this thread is dedicated, should provide some light into this question.] Quite the contrary, because of (3). Plants need unpolluted water and lots of oxygen. After that, moderate lighting and moderate input of CO2.
(3) Excess nutrients support too rapid, too stormy development of microbes of all kind. We need them, of course, but in the early phase, when plants are struggling to create roots and generally establish themselves, microbes can be and often are dangerous. Typically, bacteria (unlike fungi) cannot enter plant tissues. But they can enter if the tissues are mechanically damaged. This inevitably happens when transplanting, and fixing these damaged tissues is the first task of newly planted plants. [Some microbes are beneficial in this respect. Tank D in this experiment is an attempt to evaluate the effect of such selected microbes.]

what do you mean about "unsuitable" organic matter?

Insufficiently decomposed organic matter. A fresh dead organic matter is full of attractive nutrients. Microbes can rapidly proliferate when such a rich matter is available. While in matured substrates, there's a lot of detritus consisting of the least attractive remnants of dead organic matter. Such a matter generally consist of mere carbon, oxygen and hydrogen. Not very interesting for microbes because they must maintain Redfield ratio, while higher plants don't; supportive tissues (cellulose, lignin) are typically poor in key nutrients (N, P, micros). Similarly, microbial biofilms are polysaccharides poor in nutrients.
As a result, this "good" detritus does not support explosive proliferation of microbes (with increased oxygen demand), but it serves as an adsorbent of nutrients and colonization area for microbes.

the beginning of a tank is the most difficult time for people and I think there's value in any product or technique that can help you get through the first weeks as smoothly as possible.

I agree. The first months are the most difficult. I'd welcome a "foolproof" method. But my experience suggests that ample amount of nutrients and organic matter is not the way to go.

I frankly did not see any Ammonia Spike with ADA Amazonia II.

I did and duly recorded it in this experiment. I readily admit this is my first and only experience with ADA Amazonia v. 2 (without Amazonia supplement), but the ammonia spike is clearly pronounced.