Protekt cloudy?

[EclipseFour20]

Aveng & Only,

Let me respond with some tables & graphs.

First let's post the Table Aveng is referring to from the Silicon Conference. I have two comments about that Table--
1. The Riice industry requires slag sources of Si (which are not "organic") to be at least 20% soluble--but also contain industrial contaminants including traces of heavy metals.
2. Notice Potassium Silicate is almost last (3rd from the bottom) and was bested by the lower grade DE tested (FSF is 41.6% Si).

And in that same Conference Report Aveng referred to, on page 152 there is also a study on AgriPower Enhanced DE (sourced from fresh water diatoms and finely milled, just like FSF). Instead of performing one type of extraction test (like the above table), they did three (alkaline, acid and neutral extraction techniques) and notice that slags did not do so well in these group of tests.
First those graphs--

And that paper's conclusion--

The inclusion of AgriPower Silica into the nutrition program of several crops as a base soil conditioner ahead of planting delivered significant improvements in crop productivity and the gross margin per hectare grown. This was attributed to diatomaceous earth‘s ability to increase nutrient retention and plant uptake, improve moisture retention and deliver plant available silicon.

NPK (Nitrogen, Phosphorous, Potassium) based fertilisers are often considered a necessary part of intensive crop cultivation to improve crop production. Problematically, these fertilisers are a major source of water pollution due to Australian soils‘ susceptibility to leaching. The initial results presented in this paper support the argument that AgriPower Silica could improve the soil retention and plant uptake of these key nutrients, indicating the potential for AgriPower Silica to displace a significant portion of NPK fertilisers. A reduced requirement of urea and phosphate inputs would provide an economic benefit and reduce the environmental impact of these fertilisers. AN improved crop yield due to the application of AgriPower Silica similarly provides an economic benefit.

Calcium Silicate slag as an industrial by-product is a proven Si-rich amendment, however, it carries the risk of polluting soils and natural waters. An Enhanced AgriPower Silica was developed based on the natural AgriPower Silica. This product is free of the contaminants typically found in slags and delivers a significant amount of plant available silicon in all the four soils tested. The level of Si in the most Si-deficient soils was increased by 120% and therefore stands to benefit significantly from the Enhanced AgriPower Silica.

 

[EclipseFour20]

And....(part 2 as there is a limit of 5 images per post) referring to the fourth document linked in my first post in this thread (post #7), we have this study that used not 1, not 2, not 3....but (drum roll please)....SEVEN different extraction procedures PLUS an elemental analysis of the Si materials tested.

Please note the numbers for DE and Wollastonite.

And which seven extraction procedures were used?

Hmmmm, it appears DE/FSF is looking rather good! And then we have these words from the AgriPower study--

To date, a large amount of the reported research, field trials and commercial applications have been with calcium silicate slags, an easily obtained by-product of furnaces. Silicate slag has been used extensively in the USA; however, slags can be variable in composition and although they have high concentrations of total Si, often only a small proportion is easily solubilised (Gascho, 2001). An important consideration with silicate sources derived from industrial by-products is the possible high level of heavy metals associated with their origin or processing (Berthelsen et al, 2003). These are not only toxic to plants but leach into waterways causing environmental damage. Likewise, cement and cement building board waste can contain heavy metals (Muir et al, 2001).

Amorphous diatomaceous earth (DE) is known to be a good source of plant available silicon as amorphous silica is more easily solubilised than crystalline silica. Amorphous DE is also expected to exhibit soil-conditioning properties given its high water holding capacity, without the heavy metal contaminants of slags.

Like I said earlier, FSF has many attributes that are beneficial for plants--above and beyond providing PAS.

 

[Avenger]

2. Notice Potassium Silicate is almost last (3rd from the bottom) and was bested by the lower grade DE tested (FSF is 41.6% Si).

Like I said, you quote stuff you do not comprehend. As I have suspected, it appears you can not discern between soluble potassium silicates(dissolved water glass) and pyrophyllite-biotite mica. Either that you you confuse them on purpose to make your point.

According to AgriPowers sell sheet, 0.5% of its total silicon content(89% by weight) is available Si.

Then from this article in the Journal Of Plant Nutrition: http://www.tandfonline.com/doi/abs/10.1080/01904167.2011.533327#.Vaun_nnbKCg

They determine that the best estimate for PAS from liquid products containing soluble silicates is the Total Si. So they are saying that all of it is available already because it is already in solution.

For the liquid fertilizers, all the Si is almost completely soluble and, in this
case, the extractor used for estimating plant available Si is not so important
since all Si is available.

For the liquid Si sources, the correlation coefficient for plant Si uptake
was 0.94∗ and 0.92∗ for total Si and resin method, respectively (Figure 3). The
strong relationship between liquid Si source and plant Si uptake is due to the
high amount of water soluble Si content. Thus, the best method suggested
for evaluating plant available Si in the liquid fertilizer sources is total Si
(HCl + HF).

CONCLUSIONS
The efficiency of the extraction method was governed by the whether or
not the Si fertilizer was solid or liquid. Based on the correlation coefficients,
the best extractors for estimating available Si in solid fertilizer was Na2CO3
+ NH4NO3, which, depending on the source, estimated between 4 and 19%
Si. For liquid fertilizers, the total Si (HCl + HF) was preferable since most Si
in the liquid fertilizer is already available and the total Si extraction and Si
uptake by the plant are significantly correlated. The current study provides
regulatory agencies data that two extractors are now available for estimating
plant available Si from fertilizers depending on the physical property of the
materials (solid or liquid).

 

[EclipseFour20]

As to why the extraction results vary, the answer you get depends on who you talk to. Here is one perspective suggesting why different testing techniques on similar amorphous Si samples do not produce good correlations (hence the variance in the above graphs/tables).

4.2 The phytolith pool

The quantification of the phytolith pool in soils is based
on the physical and chemical properties of amorphous
opal A. Other biogenic amorphous silica particles can be
found in soils such as diatoms frustules and the
camoebian testates (Cary et al. 2005). Depending on the
target (biogenic silica, plant-available Si, or amorphous Si
as a whole), the aim of the study, and the scientific
discipline, different approaches have been developed to
identify and quantify amorphous silica in soils (Sauer et
al. 2006).

The gravimetric method (Kelly 1990), which separates
particles of amorphous silica from the rest of the soil using
heavy liquid flotation, allows for the observation and
quantification of amorphous silica particles and phytoliths.
The phytoliths represent generally 0.7–3% of the forest soil
dry weight (Bartoli 1985). Jones and Handreck (1967)
observed 1–2% of phytoliths in grassland soil, while soil
horizons resulting from phytolith accumulation have also
been described (Meunier et al. 1999).

An alternative technique to quantify the phytoliths in
soil is by solubilization. Contrary to the gravimetric
method, this is a destructive method so that the
proportion of phytoliths vs. other amorphous silica
particles cannot be assessed. Saccone et al. (2007) used
alkaline extractions (NaOH and Na2CO3) originally used
to quantify diatoms in marine sediments (Demaster 1981).
Chemical and gravimetrical techniques on similar samples
do not necessarily give good correlations (Saccone et al.
2007), indicating that the methodology should be improved
if phytoliths are to be quantified. Other nonalkaline
extractants do not solubilize phytoliths and
usually dissolve less than the alkaline ones (Saccone et
al. 2007), but they may be used (or have been used) to
quantify immediately plant-available Si in specific soils
(e.g., Liang et al. 1994).

The depth distribution of soil phytoliths is variable,
but generally, the highest concentrations are found in the
topsoils of undisturbed soils (Saccone et al. 2007;
Sommer et al. 2006) and decrease with depth. This
distribution reflects the equilibrium between the rate of
phytoliths input via litterfall and the rate of phytolith
output via dissolution.

Source: https://hal.archives-ouvertes.fr/hal-00930510/document

Aveng, as to your theory that Potassium Silicate is superior to FSF, I believe there at least about half dozen different Potassium Silicate fornulations with another dozen or so material sources, so now all you have to do is find a few studies that support your hypothesis that AgSil is superior to all other Potassium Silicates. Then find a few studies that conclude Potassium Silicate is superior source of Si when compared to DE. Right now, you have not produced anything to suggest differently, so I think DE is currently the winner by default. Confused....lol, nope--but I am curious if there is ANY SCIENCE to support your opinions.

 

[EclipseFour20]

...According to AgriPowers sell sheet, 0.5% of its total silicon content(89% by weight) is available Si.
...

And...AgriPower Silica "specification sheet" states: Plant Available Silica is 1212 mg/kg.

Source: http://media.wix.com/ugd/73c92b_7665219c465d4dc98de4fef8dc036dd9.pdf

I wonder how low AgSil numbers are--comparatively speaking of course. Do you have them Aveng? If there are none--then, IMHO, AgSil numbers should be what is described as "Potassium Silicate" for purposes of our future discussions; just as I do when the study says "DE" or "amorphous Si"--I accept those as a minimum even though FSF is far superior than all the half dozen or so qualities/grades of DE that are marketed (source--fresh vs seawater, density--granulated/chunks vs fine powder, type--calcined vs uncalcined, purity, etc).

 

[EclipseFour20]

After all this talk about PAS, Si%, solubility, etc, isn't the real quest is to discover exactly how cannabis plants uptake and deposit PAS?

Some believe Si deposition is controlled by the plant, some believe it is a result of water intake. The following is from the attached 2014 research paper titled: "Phytoliths in Plants: A Review". It sums very nicely what some believe regarding "plant uptake and deposition of PAS".

Uptake and Deposition of Silica
Silicon is taken up by the roots in the form of silicic acid (Si (OH)4), an uncharged monomeric molecule, when the solution pH is below 9 [44]. The process starts when soluble silica is absorbed by the plant roots along with other elements occurring in the ground water and carried upwards to the aerial organs in the transpiration stream via the water conducting tissue, the xylem. It is presumed that root hairs assist in the uptake of nutrients and water from the soil [45]. But Ma et al. (2001) [46] found that lateral roots but not the root hairs are responsible for Si uptake in rice. In a study they investigated the role of root hairs and lateral roots in Si uptake using two rice mutants, one defective in the formation of root hairs (RH2) and another in that of lateral roots (RM109) and the wild type. Their results clearly show that lateral roots contribute to silica uptake in rice while as root hairs do not.

Through mechanisms that are incompletely understood but that increasingly appear to be under a considerable genetic and metabolic control [47, 48], some of the silica is eventually laid down in the growing plant as solid, SiO2 in-fillings of cell walls, cell interiors (lumina), and intercellular spaces. Most of the soluble silica initially absorbed from the ground water is transported to aerial structures, where it may result in the heavy impregnation of both vegetative and reproductive structures. Certain plant taxa also heavily silicify their underground organs [29].

There are two major ways by which plants are thought to absorb soluble silica, and although there has been debate concerning which is most important, it is now clear that both are critical to the transfer of monosilicic acid from ground water into roots and then to aerial organs of the plants. The two mechanisms are:

Active Transport
The active transport of monosilicic acid by metabolic processes is in strict control of plant. In this uptake, plant expends energy metabolically during silica absorption. When a plant expends energy in this manner, it is choosing to allocate a portion to a finite set of resources to use silica in some way, and, in itself, it indicates a designated functions for the silica so absorbed, either in its soluble or in its solid state [16]. Active uptake is dominant in rice, sugar cane and wheat [49, 50]. Root exudates that prevent silica polymerization may aid in active uptake, their by allowing more transmembrane movement. The compound poly-2-viny pyridine-1-oxide may act in this manner, which explains its effect of increasing the amount of leaf silicification in rice [51]. Okuda and Takahashi (1964) [52] first showed that silicic acid appeared to be entering the xylem sap of rice shoots against a concentration gradient, a feature pointing to active transport. Okuda and Takahashi (1962) [53] documented that in case of rice silicon accumulation is an active process which is seriously inhibited by respiratory inhibitors like, sodium cyanide (NaCN) and metabolic transporters, providing a clue for the involvement of active transport of silica in plants. The plants with an active Si uptake uptake system and transport are characterized by a much higher intake of Si than of water, resulting in Si depletion in nutrient solutions [46, 54].

Van der Worm (1980) [55] demonstrated active uptake in sugarcane and rice, and subsequent studies by Jarvis (1987) [56] and Ernst et al. (1995) [7] confirmed the importance of active uptake in grasses and sedges, where passive processes were also often at work in different areas of the plants.

Passive Transport
The passive, non-selective flow of monosilicic acid along with other elements from groundwater is through transpiration stream. In this pathway the plant expends no energy metabolically during silica absorption [29]. Plants with a passive mode of uptake take up Si at a rate that is similar to the uptake rate of water; thus, no significant changes in the concentration of Si in the uptake solution is observed [53, 46].

The evidence for passive silica uptake is considerable. In a classical laboratory experiment, Jones and Handreck (1965) [49] showed that they could closely predict solid silica content, expressed as a percentage of the total dry weight of the plant, by knowing simply the concentration of silicic acid in soil solution and the amount of water transpired. Such a close relationship between movement of water and amount of silica that a plant eventually solidifies is expected to be under a passive control. On an average, plants absorb from 50 to 200 kg of Si ha-1. Such values of silicon absorbed cannot be fully explained by passive absorption (such as diffusion or mass flow) because the upper 20 cm soil layer contains only an average of 0.1 to 1.6 kg Si ha-1 as monosilicic acid [57].

Despite the much work conducted over the last two decades, mechanism for silica uptake and transport in plants still remains poorly understood, Because an absence or a very low concentration of phytoliths has been found also to be the characteristic of many plants, it stands to reason that they probably have some mechanism for either the rejection and entry of silicic acid at the root surface or preventing its passage from the roots to the aerial organs. Parry and Winslow (1977) [58] experimentally studied such kinds of mechanisms in peas (Pisum sativum), which do not produce many phytoliths. Root removal in pea seedlings resulted in the high concentration of silicon but not individual, solid deposits of it in leaves and tendrils, whereas plants grown in silica solution with roots still intact showed no such accumulation. This finding indicates that a mechanism of silica rejection occurs in the roots and is probably located near the outer surface of roots since no silicon was detected within the roots of intact plants.

After uptake, dissolved monosilicic acid moves across the cortex of the root until it reaches the endodermis. The endodermis has long been considered to control water and solute movement into the vascular tissues [59]. The casparian bands block apoplastic flow in young root tissues, and only flow through symplast is possible. The secondary stage of endodermal development involves the formation of suberin lamellae around the inside of the cell. It has been recently suggested that this layer is permeable to water [60]. If this is so then apoplastic flow occurs within this layer, inside the casparian bands in older roots. Nevertheless, the endodermis undoubtedly constitutes the major resistance to monosilicic acid flow through the grass roots, and it is here that many of the root silica deposits are found [61].

Frey-Wyssling (1930) [62] suggested that the silica accumulation at the aerial plant surfaces is due to transpiration. Transpiration has been implicated in both the conduction and content of silica in aerial portions of gramineous and other crop plants. The relevant earlier studies have been reviewed by Jones and Handreck (1967) [63]. Developing silica cells in the leaf sheath of wheat (Triticum aestivum) have an apparently normal cuticle but differ from surrounding cells in having smaller nucleoli and thinner outer cellulose walls [64]. Thin outer cellulose walls may result in higher rate of transpiration, facilitating an influx of silica as monosilicic acid [63]. Sangester and Parry (1971) [65] and Raven (1983) [66] advocated transpiration or water loss as a major factor in silica polymerization. In some species, greater amounts of silica are deposited in those regions of the plant were water loss is maximum. However, this is not always the case, since silica is often deposited in tissues that restrict water loss, such as sclerenchyma. Indeed the association between the development of silica bodies and sclerenchyma requires further exploration, since the two are often associated; for example, in orchids [67]. The objection to these hypotheses of passive silica deposition is the difficulty of explaining the pattern of typical silica deposition. However, this could bring about as an indirect result of changes in the structure or biochemistry of potential silica-cells. Prat (1948) [68] suggested that developing silica-cells undergo premature senescence, which is accompanied by a drop in their pH. Such a change could initiate silica precipitation, as silica sols are unstable with respect to changes in pH level, being particularly susceptible to the gelation at pH 5.5. Alternatively, if the structure of the external wall or the cuticle of the cells allowed more rapid cuticular transpiration to occur, silica solutions would concentrate in these cells, resulting in the gel and opal formation.

It is believed that silica accumulation is controlled by plants to increase the mechanical stability of their tissues and to provide protection against microorganisms and herbivores [63, 69]. Thus there are two different hypotheses to explain silica accumulation in plants. If silica accumulation is as a result of water consumption, plants could be expected to accumulate silica not only during growth but also after maturation. If on the other hand, silica plays an active role in the protection of plants, it could be expected that accumulation occurs during plant tissue differentiation and cease when plants are mature.

Commoner and Zucker (1953) [70] proposed that the appropriate enzyme system for deposition might be synthesized or segregated in some cells only. However, till date no enzyme active in silica deposition is known. Molecules which are active in other aspects of silica metabolism in grasses, e.g. in silica uptake [71], may participate in deposition process.

Silica accumulation is characteristic of some plant families, whereas others produce little or no silica. Species with little silica control the amount of silicic acid that enters the root or passes from the root to aerial tissues of the plant [29]. Jones and Hendreck (1969) [72] proposed a hypothetical barrier in root epidermal cells of clover (Trifolium incarnatum) that restricted the flow of silicic acid into the transpirational stream. Experiments conducted by Parry and Winslow (1977) [58] on pea seedlings (Pisum sativum) showed that there is some mechanism at the root surface which disallows the passage of monosilicic acid into the root. In other species, such as Vicia fabia and Ricinus communis, a layer of fatty substance on the root-hair surface may form the barrier [58].

There are substantial differences in the silicon concentration in plant kingdom. The range of its concentration is 0.1-10% Si on a dry matter basis [73, 74]. Plant species older in evolutionary sense (diatoms, cyanosis, horse tails, and ferns) contain more Si than plants that emerged later. Among higher plants, species from gramineae and cyperaceae families accumulate Si in large amounts and are considered as Si accumulators (higher than 1% silicon on dry weigh). Rice and other wetland grasses are an example of Si accumulators. Most dicotyledonous plants contain less than 1% of Si on dry matter (non-acumulators). A third distinguishable group of plants has intermediate plants, Jones and Handreck (1967) [63] listed dryland grasses such as rye and oats. However, recent studies indicate that a high silicon concentration is not a general feature of monocotyledons species [75]. Most Si is deposited in cell walls of roots, leaves, stems and hulls, where it may form a thin layer consisting of silica gel (SiO2.nH2O). Investigations conducted by Ma et al. (2003) [76] on grains of 401 barley varieties showed that the variation in Si concentration in grains is controlled genetically. More than 805 0f the total Si concentration in grains is controlled genetically. More than 80% of total Si was localized in the hull and its amount ranged between 15.343 and 27.089 mg Kg-1 in tested varieties.

Grasses and bamboos are known to have large deposits of silica in the tissues of leaf blades and inflorescence bracts. It is reported that the silica content in mature leaves of Phyllostachys pubescens increases rapidly during the first early growing season, levels off during the first autumn, and then increases again during the following early spring [77], whereas it never increases in P. bambusoids [78]. However, it is unclear whether the increase in the second growing season is the result of leaf ageing or to reactivation, because the life span of leaves in both the species is only one year. In contrast, leaves of Sasa veitchii have a life span of approximately 2 years and continuously accumulate silica throughout their life, not only during the developmental process but also after maturation. This study clarifies the season- dependant changes in the silica content, and shows that the accumulation pattern (rapid in spring and summer and slow in winter) is repeated during the 2 years of life span. These facts support the first hypothesis that silica deposition is a result of water uptake by plants [79].

Silica deposition at the tissue level was investigated in young, mature leaves of Pleioblastus chino (about 1-2 months after leaf expansion), and was found to be densest in the epidermis and least in the mesophyll and vascular tissues [80]. If silica deposition is as a result of water uptake by the plants, silica deposits would be expected to be denser in the mesophyll, where a substantial amount of water transpires directly, than in the epidermis. However, mesophyll cells do not accumulate much silica perhaps because they are prevented from doing so as they are actively involved in photosynthesis. Consequently, these results support the second hypothesis that the silica deposition in tissue systems is positively controlled by the plant.

...

Trichomes
Trichome is a common term used to designate all unicellular or multicellular appendages. Metcalfe (1960) [23] classified hairs on grasses into three major groups; macro-hairs, micro-hairs and prickle hairs. Prickle-hairs may be hooked or straight. These trichomes point towards the apex of the plant part on which they are found. Hooked trichomes are more common on the margins of the leaf blade, empty glumes, lemmas and the axis of the inflorescence of many grasses. These trichomes are thick-walled and may have silica deposits in their lumen.

Micro-hairs are present on the epidermis of both the leaf surfaces, the abaxial surface of the leaf sheath, empty glumes, and lemmas. They are bicellular structures comprising of a basal cell and an apical cell. They are found between the veins but not over them. The basal cell of the micro-hair lies in the epidermis. The microhairs bend to a right angle to the leaf surface and point towards the apex. The basal cell has a thick wall whereas the apical cell is thin walled. The basal cell may become silicified and is identified as a pipe-shaped particle among the small particles of plant opal. The apical cell is seldom silicified [33].

 

[G.O. Joe]

Seriously, you think a solid polymer is more likely to release monomer than the aqueous K salt of the monomer. You've done some editing about the zero amount of PAS in it, while I've been writing this.



AgSil 25 has PAS measured at 72, 78, and 91% of the entire amount of Si in the solution. It is much cheaper to make than the figures provided earlier - it's just silica and potassium carbonate melted together. Has anyone measured rockwool for PAS? FSF and DE would totally fail in rockwool. Adding something with a high pH like silicate is the last thing a rockwool grow needs. Fasilitor wins that one, if it adds Si and if that's a good thing for plant matter which may be burned and inhaled.

 

[EclipseFour20]

Welcome to the dialog Joe--are you saying the FSF is a solid polymer? I don't think that would be a true statement. If you are, please explain yourself....thanks.

Long ago, I said FSF may not be suitable for all growing mediums, but for those of us that grow peat/coco/soil based mediums....FSF is an alternative. That said, I have seen several instructions on how to use FSF in hydro setups--so who knows what may be suitable or not?....until one tries.

Remember, our objective here is to provide an adequate amount of Si to our plants--which some estimate to be equivalent of 50-200kg/ha.

Can you post the source of those tables--I would love to see the science/words behind them. AgSil makes several items, I believe Aveng wants to compare AgSil 16h, the powder form not the liquid variety.

 

[G.O. Joe]

are you saying the FSF is a solid polymer? I don't think that would be a true statement. If you are, please explain yourself....thanks.

What else would it be? Also, if it's finely ground, it's probably going to get dripped out of a rockwool block. The crystallographers say diatoms analyze as silica gel. I'm not knocking silica gel - the uncrushed beads do increase ppm perhaps all that is necessary.
http://dx.doi.org/10.1007/BF00350922

Can you post the source of those tables--I would love to see the science/words behind them.

The second table is from

In this .pdf describing the newly AAFPCO approved method for determining PAS for fertilizer labeling, they show that Agsil 25 has 9.7% total Si(20.8% SiO2) and 7.6% PAS. (5-Day Na2CO3-NH4NO3 extraction method)

The first table is from
http://dx.doi.org/10.1080/01904167.2011.533327

Plants were grown for that project, to test availability. The most reliable methods known for finding PAS were used to give the numbers for soluble Si in both tables.

In any case, only so much TRULY PAS can be present at a certain pH at any given time, except maybe weird things like Fasilitor. Dump a bunch of silicate in pH 5.8 water and it's going to polymerize. The silica cycle is one of polymerization and depolymerization and more is not necessarily better. Or, soluble silicate is going to combine with Mg, Ca, etc., precipitate, and be locked out from further participation, as the data shows.

Welcome to the dialog Joe

I've been around, there isn't anything new to say.
https://www.icmag.com/ic/showpost.php?p=5689178&postcount=2

 

[Avenger]

I wonder how low AgSil numbers are--comparatively speaking of course. Do you have them Aveng?

As your self appointed research assistant I feel obligated to point out that I already posted this requested info. Though it is obvious you did not comprehend what was given to you. Thanks to G.O Joe for posting the images for your easy viewing.

I do not have any AAFPCO approved numbers for AgSil 16H, the spray dried hydrous powder potassium silicate. Though I know it is 100% soluble in water with in minutes.

I have contacted a laboratory regarding testing water and or nutrient solutions for silicic acid as well as testing of dry materials for PAS in the AAFPCO approved NaCO3-NH4NO3 method. If it is economically feasible, I will post the analysis after I have the results.

Here is the data supplied by the manufacturer:

AgriPower Silica "specification sheet" states: Plant Available Silica is 1212 mg/kg

So that is 0.12% PAS by weight for AgriPower diatomaceous earth. Where as AgSil 25 is 10.5%(HCl + HF extraction method) PAS by weight.

Welcome to the dialog Joe--are you saying the FSF is a solid polymer? I don't think that would be a true statement. If you are, please explain yourself....thanks.

WOW.

http://www.mbari.org/staff/conn/botany/diatoms/jennifer/introc.htm

Intro to Diatoms[/URL]]How a Diatom Employs Silicon

The most obvious use of silicon mentioned above is the use of silicon in the siliceous components of the cell (valves, girdle elements). The cell wall is constructed by silica deposition vesicles (SDV) with membranes called silicalemmas. The orthosilicic acid and other forms of silicon in solution are transported to theses SDVs, and polymerization occurs in order to create solid deposits of silica. This polymerization may be sparked by a change in pH or silicon in solution or a host of other factors. The SDV have extensions that become connected, allowing expansion of the cell wall and its associated silicalemma. It should be noted that silica is not laid down in the raphe slits, and it may be prevented from doing so through the presence of raphe fibers

In any case, only so much TRULY PAS can be present at a certain pH at any given time, except maybe weird things like Fasilitor. Dump a bunch of silicate in pH 5.8 water and it's going to polymerize. The silica cycle is one of polymerization and depolymerization and more is not necessarily better. Or, soluble silicate is going to combine with Mg, Ca, etc., precipitate, and be locked out from further participation, as the data shows.

Which brings us back to the opening post of this thread. Ky poured some soluble silicate into surface water that is most likely near neutral pH. If he was following the labels directions for dilution, then he was diluting it to approx. 100ppm SiO2. This is very near if not over the solubility limit for SiO2, depending on factors such as the solutions starting pH, other ions in the starting solution, temp ect. Ky's question was why does it go cloudy when he dilutes Protekt into the stream water but not his tap(ground)water.

My answer based on my experiences with soluble silicates as well as my substantial liabrary of water analysis was that the low pH of the stream water and the high dilution rate are the reason for the clouding. While precipitation with divalent cations is a concern, the stream water likely contains less than the tap water does.


cheers

 

[Only Ornamental]

...
I do not have any AAFPCO approved numbers for AgSil 16H, the spray dried hydrous powder potassium silicate. Though I know it is 100% soluble in water with in minutes.
...
So that is 0.12% PAS by weight for AgriPower diatomaceous earth. Where as AgSil 25 is 10.5%(HCl + HF extraction method) PAS by weight.
...
low pH of the stream water...

AgSil 16H is only apparently soluble in water . It forms a sub-colloidal solution which is not composed of monomers but small particles which do not sediment and behave like a solution in a bunch of tests. AgSil 16H has only ~0.78 potassium atoms per silicic acid (at least that's what I have in my notes) and hence contains even branched polymers. It should, in a 'clean&perfect' environment, dissociate completely into orthosilicic acid at a high enough dilution.
Anyway, a point I do not like with the extraction procedures is the absence of a real proof. IMHO one should determine the absolute amount of silica in soil and plant to determine how much is actually taken up during a certain time (e.g. a growing season). Does anyone know of such a work?

HCl + HF extraction does dissolve ALL silica and is used to determine the absolute silica amount, not PAS.

I still wait for him to tell us his results from the pH measurement. Before that, it's all just assumptions and speculations.

BTW silica and DE are polymers and obviously solid too. This is the basic principle and definition of amorphous silica.

 

[Avenger]

Certainly and indeed, at high concentration it is not a true solution of silicic acid, but it should, at similar SiO2 concentrations, be relatively higher in monomer than agsil 25 because of its lower SiO2:K2O weight ratio.

HOW DOES SILICATE SPECIATION VARY?
There are two major factors that influence the distribution of anions—the ratio of silica to alkali (pH), and the concentration of solids.

Moving from high alkali, low ratio products to low alkali, more siliceous high ratio products represents a change in silicate species distribution: from high monomer (Q0) content and few complex structures (Q4) to reduced monomer content and a greater number of complex structures.

The change in distribution ranges through a rise and fall in content of intermediate chains and cyclic trimers, and larger rings (Q1, Q2, Q3). At ratios greater than 2.0, colloidal structures begin to form in the solution. At very high ratios, the structures result in gelling of the solution.

Which is why I personally choose it over Agsil 25(or Protek) or Agsil 21. That and it is a powder and I prefer to handle powders over liquids.

If you can see error in my logic, please do inform.

When you dilute it and then acidify to the proper level for a working fertilizer solution, it should be plant available silicic acid.

Regarding your request for research on extraction methods and actual plant uptake, does the following satisfy your proof requirement? If so I could share the full text with you. It does not include DE.

To evaluate the capacity of the Si sources to supply plant available Si and
to determine the best extractor for estimating this availability from the fertilizer,
an experiment was conducted in the greenhouse. Rough bluegrass (Poa
trivialis, cultivar ‘Darkhorse’) seeds (0.75 g pot−1) were grown in a 50:50 vol.
mixture of sand and Metro-mixR
300 series (Sun Gro Horticulture Distribution,
Inc., Bellevue, WA, USA), which had an 0.5 M acetic acid (HOAc)-
extractable Si value of 10 mg L−1. 100 g ofOsmocoteR
(Scotts Co., Marysville,
OH, USA) controlled release fertilizer 14-14-14 [nitrogen (N), phosphorus
pentoxide (P2O5), and dipotassium oxide (K2O)] was added. Plastic pots
(10 cm diam.) were filled with this root-zone mixture and amended with
each Si fertilizer source at a rate equal to 600 kg ha−1 of Si. The actual
amount applied per pot were as follows: Wollastonite W10: 0.56 g pot−1;calcium silicate from the U.S.: 0.88 g pot−1;magnesium silicate: 0.47 g pot−1;
Excellerator: 1.06 g pot−1; silican gel: 0.33 g pot−1; calcium silicate from
Canada: 0.39 g pot−1; 00 –00-12 + Si: 3.33 g pot−1 and three liquid sources
of potassium silicate, K53: 1.07 g pot−1; K120: 0.85 g pot−1, and AgSil: 1.14 g
pot−1).
The experiments were maintained in the greenhouse (26 –30◦C) and
watered as needed. Twenty four days after seed germination, plants were
collected for dry matter weight. Tissue was dried, ground in a Wiley mill
(Thomas Scientific, Swedesboro, NJ, USA), and passed through a 40-mesh
screen. Silicon content in the plant was determined using a slightlymodified
autoclave-induced digestion procedure followed by automated colorimetric
analysis (Elliott and Snyder, 1991). Turf biomass was determined along with
Si accumulation. The percentage of Si extracted from the Si sources was
correlated with the total Si accumulated by P. trivialis.
The experiment was arranged in a randomized complete block design
with 3 replications per treatment. The experiment was repeated twice. Data
were analyzed using SAS (SAS Institute, Cary, NC, USA) and subjected to
ANOVA and linear regression procedures.

And then finally your point about "HCl + HF extraction does dissolve ALL silica and is used to determine the absolute silica amount, not PAS." I refer you to the conclusions from the same article the above was quoted from.

http://www.tandfonline.com/doi/abs/10.1080/01904167.2011.533327#preview

CONCLUSIONS
The efficiency of the extraction method was governed by the whether or
not the Si fertilizer was solid or liquid. Based on the correlation coefficients,
the best extractors for estimating available Si in solid fertilizer was Na2CO3
+ NH4NO3, which, depending on the source, estimated between 4 and 19%
Si. For liquid fertilizers, the total Si (HCl + HF) was preferable since most Si
in the liquid fertilizer is already available and the total Si extraction and Si
uptake by the plant are significantly correlated. The current study provides
regulatory agencies data that two extractors are now available for estimating
plant available Si from fertilizers depending on the physical property of the
materials (solid or liquid).

 

[Only Ornamental]

...
2. Notice Potassium Silicate is almost last (3rd from the bottom) and was bested by the lower grade DE tested (FSF is 41.6% Si).
View Image
...

Ha, I just realised that the potassium silicate on that list isn't the potassium silicate you're thinking of. It's an insoluble mica (micas are known to be not the best source for silicium as this one is tightly bound in crystalline layers), not something like AgSil .

 

[Avenger]

results are in

makes me reconsider my choice of AgSil 16h over AgSil 25.

 

[Kygiacomo!!!]

results are in

View Image

View Image

makes me reconsider my choice of AgSil 16h over AgSil 25.

very interesting bro! i found a lab report from the same company as this one for Aptus Fasilitor and it only had 0.85% soluble silicon,so this means that Agsil 16 is by far the best product at a fraction of the cost. i just wonder why all the claims out there that Fasilitor is far superior. this leads me to think that Aptus fasilitor has something in it that is more then just a silicate. thanks for the post and lab reports +rep

 

[40AmpstoFreedom]

Awesome thread you don't get stuff like this on any other site. Thanks to all contributors, this took a lot of time from all of you. It just amazes me day in and day out how poorly utilized all of us are in this prohibition.

 

[stoned-trout]

I would have to agree....yeehaw

 

[Avenger]

very interesting bro! i found a lab report from the same company as this one for Aptus Fasilitor and it only had 0.85% soluble silicon,so this means that Agsil 16 is by far the best product at a fraction of the cost. i just wonder why all the claims out there that Fasilitor is far superior. this leads me to think that Aptus fasilitor has something in it that is more then just a silicate. thanks for the post and lab reports +rep

The lab report is from the same lab that, for lack of a better term, helped come up with the AAFPCO approved 5 day testing method for Plant Available Silicon determination in fertilizer materials. It is the lab from this white paper:
http://www.ingentaconnect.com/content/aoac/jaoac/2013/00000096/00000002/art00007?crawler=true

In my opinion, all the hoopla about Fasillitor and other stabilized silicic acid liquid concentrates, being superior comes from bro science and a real misunderstanding of the facts.

There most certainly is something in Fasilitor and other stabilized silicic acid products that is more than just silicon source material. The formula is ~40% PEG400, along with a good dose of hydrochloric acid.

These SSA formulas, from my understanding, were really formulated for foliar application. With so much of the formula being a surface active agent(PEG400) I can see how they would work well at penetrating the waxy cuticle layer on the leaf surface.