Who did make this? He doesn’t even know what gram per liter is, reporting based on useless molarity which no chemist use 
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Hi @lefthandseeds @neogitus @Dirt_Wizard @herojuana.tom @HolyAngel @SeymourGreen …just a heads up on certain development with the recipe I posted earlier.
I managed to find its author @immygod and had been chatting with him regarding his formula and asked him to join OG.
He has engineered the formula to be ph buffered for both tap and ro with the inclusion of silica in the feed as well.
He does certainly does know his math pretty well and also quite a bit on chemistry…
This guy’s a genius with the creation of these stock solutions. Pls do ask/question him regarding his formula and let’s hope one of us can actually work on this formula to prove its efficiency…
Cheers everyone…
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Below are some notes I’ve taken from our conversation on an app earlier based on the above posted formula. We haven’t discussed much on the micro mix (stock #5)
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taking purity in to the account
KOH @ 8.95 g/l
SiO2 @ 9.58 g/l
K2CO3 @ 17.28 g/l
H3PO4 @ 36.04 g/l
Ca(NO3)2,4H20 @ 210.85 g/l
Mg(NO3)2,6H20 @ 80.94 g/l
K2SO4 @ 55.00 g/l
NH4NO3 @ 10.16 g/l
KCl @ 2.34 g/l
KOH dissolves in cold water easily. but after adding SiO2 it is not going to dissolve soon if temperature solution is low. To dissolve SiO2 completely u need the temperature to be more than 80° C for that SiO2 to dissolve in KOH solution in a half an hour or a day or so at room temperature.
I dissolve KOH in 100 ml at room temp. then I add SiO2. then I add 400 ml boiling water. I stir for 10-15 min. then I add 300 ml more boiling water to back to 80C again and continue string. and finally top off to 1.00liter
Note: dissolving koh in glass container could cause the silica in the glass to react with solution. Preferably use plastic hdpe or no.2 plastic.
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2, 2, 3, 2 ml/l of stocks 1-4 will give u
107 ppm N
19.4 ppm P
73 ppm K
105 ppm Ca
22.5 ppm Mg
20 ppm S
and 4,4,4,5 of stock 1-4 will give u
147 ppm N
38.8 ppm P
165 ppm K
140 ppm Ca
30 ppm Mg
50 ppm S
Note: this is without the micro mix stock#5 (any micro mix is probably compatible I’ve heard with appropriate dilution and the right chelates. Will update on this further)
the plan is to sacrifice faster grow using less N and P during veg to get healthier looking plants and more compacted ones. these mls are just a suggestion. VPD and gower preference dictate the amount is needed.
with these 4 stocks u can change NPK ratio easily.
#1 has pH Up formula
#2 has pH down formula and alkaline remover from pH electrode (pH probe cleaning solution)
#3 is coco buffering formula.
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calcium nitrate has chemical formula Ca(NO3)2. but u may not find it anhydrous. what u probably find is calcium nitrate tetra hydrated and magnesium nitrate hexa hydrated
Ca(NO3)2,4H2O
Mg(NO3)2,6H2O
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I saw u talk about MPK. so let me explain.
nitrate and sulphates are conjugate anions of strong Nitric and sulphuric acids. salts containing nitrate and sulphate are almost neutral or tiny acidic or basic depending on cations of the salts and they will not effect pH much when they add to the solution. they are also has almost no resistance against pH changes… wild and free. but phosphate salts are different as phosphoric acid is a weak acid. when u add something containing phosphate, a group of all other phosphates family will stay in equilibrium depending on pH. phosphates in a solution resist changes in pH.
phosphate family:
phosphoric acid molecule H3PO4
dihydrogen phosphate anion
H2PO4(1-)
hydrogen phosphate anion
HPO4(2-)
phosphate anion
PO4(3-)
phosphoric acid is a weak acid and always decrease pH But not as Nitric or sulphuric acid at the same Molarity.
KH2PO4, is slightly acidic in hydroponics.
K2HPO4 is basic high enough to bother us.
K3PO4 should not be use in hydroponic. it is strongly basic.
Note: DONT touch any of the stock solutions directly!
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For ph electrode storage solution, dilute KCl @ 163.25gms/litre
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That’s it for now.
Tagging @immygod for further improvements/clarifications and for queries to be answered if any…
solid salts I use have +98% purity except for H3PO4 which is 85% liquid. stock #1 is strongly alkaline. Using it at 2ml/ltr raises pH to 10 when RO water is used. stock #2 is acidic enough which have to be used the same amount as stock #1 using RO water. 2 ml/ltr of #2 will drop pH to 6.3 after equilibrium. if u want lower pH use less that #1 or more than #2. You may find your K2SO4 doesn’t dissolve well. No problem, it’s OK. final solution when RO water, 0.05 mS/cm, is used is about 1.2 mS/cm @ pH 6.1 efter equilibrium with 2, 2, 3 and 2 ml/ltr of #1-4. these doses are just a recommendations. The amounts are needed depend on strain, stage of grow, VPD, CO2 concentration and user preferences, independent from light level.
My KCl storage solution is 260 g/ltr not 163
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Greetings
Got one question
It is about making dipotassium phosphate.
I have KOH and KH2PO4. I should mix the same molar amount to get dipotassium phosphate
KOH + KH2PO4 → K2HPO4 + H2O
Since I don’t have such a precise scale, it is a problem for me to determine completely accurate amounts.
If I do it in distilled water, with a slightly higher molar amount of KH2PO4, can I be sure that all the KOH will react?
If I dehydrate the mixture till crystals start to formate, will those first crystals be KH2PO4 (given that it has a much lower solubility in water), and in this way purify the final K2HPO4 solution a bit?
Yesterday i mixed a solution and replicate Jack 321.
I was suprised how low ph was. It was under 5. So maybe there is space to play with dipotassium phosphate in future combinations
But that is less important goal. First one is to play a little.
Thanks
Pannonian
They use moles because its a standardized measurement and that will let people manipulate nutrient concentrations a little easier than if you just do grams. There is a little more stoichiometry involved to get to actual concentrations of nutrients plants can use, but the mole is standardized.
I have also long suspected this is because academics are mostly insecure and have to remind people of how smart they are constantly or they will be forgotten.
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