That’s why watching the plants is so important. 
InTheShed Grows Inside & Out: Jump In Any Time
The calmag is to balance the silica and keep N:K in the right ratio. But yes, it can be considered a bit targeted. It works though, no doubt.
I would cut the silica/calmag for hydro, mainly from the silica causing pH to want to be high. Haven't found a workaround for that part yet. I'd like to find a way though, as I agree that MC could use a little more silica. I'll have to dig around and see if there is a brand or something that doesn't cause as much of an upswing as the protekt does.
That’s why watching the plants is so important.
Bingo.
Feed charts are a guide, not a rule.
That I do. Anytime after the second true set of leaves as you mentioned and your safe for feeding. A dose of 2g like felipe mentioned is standard from their calculator and it's hit and miss after that
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It's so cool that you stop by when I put up the MrS signal!
I'm not as fast as i used to be. Everything's hurry up and wait right now.It's so cool that you stop by when I put up the MrS signal!
BTW, like MrS, I have v1, and I adulterate my MC because I have the room to be able to add silica with something like protekt (currently 3ml/gal) without blowing the K out. And I add a little Calimagic (currently 1.5ml/gal) because my tap water is only 30ppm tds. 
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Once I can get my hands on some more distilled water, I will be testing to see how much of diatomaceous earth is soluble. It won't tell me what percentage of that percentage is available Si, but it's a start.
Will be interesting
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I was thinking 10 grams DE in 100 grams water. Mix well for a couple of minutes and let it settle out. Then carefully pour off the water and strain the rest through a coffee filter. Evaporate the water from the sediment (in the oven?) and re-weigh. That should give me the dissolution percentage.
Is most of the rest of that plant-accessible silica?
Is most of the rest of that plant-accessible silica?
Silica or lime maybe
The Celt
Well-Known Member
My understanding of the research papers I had read, that it was what they referred to in one as flowable (bioavailable) and the other said that the silicon in it was soluble and became a silica acid which the plants can use.
I use it in my grows always and have thick strong stems, but I also grow in LOS.
I use it in my grows always and have thick strong stems, but I also grow in LOS.
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According to Wikipedia:
The typical chemical composition of oven-dried diatomaceous earth is 80–90% silica, with 2–4% alumina (attributed mostly to clay minerals) and 0.5–2% iron oxide.
So mostly silica it seems.
But the question is how much of the silica in the DE is soluble, because the rest is just particulate matter which can't be absorbed by the roots regardless of the substrate.
Is there no other source of silica other than DE when you build your soil? And do you cook it first? That would completely change the calculus.
I’m thinking Kelp is a good source of silica in organic soil mixes.
The Celt
Well-Known Member
No, DE is the only major source of silica other than what might be locked up in alfalfa which is a major component of my soil.
As for cooking, definitely, with the major components being 2 bales of peat and 25kg (55lbs) of alfalfa, it cooks for 4 to 6 weeks before I even think of using it, I’ve seen internal temps as high as 150F.
Microbes will break down SiO so it’s plant available, but it is a slow, slow process.
How are you composting your soil?
I use a tumbler for the outdoor garden. Works a treat.
I use a tumbler for the outdoor garden. Works a treat.
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.Is alfalfa high in Si? Because if it is that would add a lot to the soil during cooking.
Either way, the real question here is about plant available soluble silica from DE.
The Celt
Well-Known Member
I mix mine up in big bins, was a 300gal tote I cut in 2.
I split the alfalfa pellets into 2 (1/2 each tote) and soak them in water and LABs to break them up and start the decomp process. After well soaked and raked around to make the pellets into meal, I add my lime, bloodmeal, bonemeal, DE, kelpmeal and PNO3 and mix well.
Then it get combined into one tub to cook for a few weeks or more, I will use it when the internal temps are the same as ambient.
I split the alfalfa pellets into 2 (1/2 each tote) and soak them in water and LABs to break them up and start the decomp process. After well soaked and raked around to make the pellets into meal, I add my lime, bloodmeal, bonemeal, DE, kelpmeal and PNO3 and mix well.
Then it get combined into one tub to cook for a few weeks or more, I will use it when the internal temps are the same as ambient.
The Celt
Well-Known Member
UrineYou're in the wrong thread then mV
Is alfalfa high in Si? Because if it is that would add a lot to the soil during cooking.
Either way, the real question here is about plant available soluble silica from DE.
I thought MV was asking about my soil lol
As for alfalfa, whatever Si it uptook growing would be bio available but how much, not a clue.
The Celt
Well-Known Member
OK, so did a quick search, and DE is most soluble at pH greater than 9, which means in a DWC grow it may not help. In any other medium, the plants roots will adjust “local” pH to make available what it needs.