is my cs working?

[fryge]

I used the crystal form, I didn't have any issues weighing the right amount. ofcourse powder would've been a little easier, but I got the crystals.

one thing to pay attention to though if it's the anhydrous or pentahydrous form. that recipe posted everywhere uses the anhydrous form, while I found only pentahydrous for sale.

it doesn't matter for making sts, it's exactly the same just with some water molecules bound into the crystals, but you have to slightly alter the weights you use. if you know molar calculations it's pretty easy to calculate the conversion factor yourself, but if you don't, I still have my enveloppe with calculations laying around here, and the conversion factor I calculated is 1.57 times the weight going from anhydrous to pentahydrous.

 

[seedlingstarter]

I used the crystal form, I didn't have any issues weighing the right amount. ofcourse powder would've been a little easier, but I got the crystals.

one thing to pay attention to though if it's the anhydrous or pentahydrous form. that recipe posted everywhere uses the anhydrous form, while I found only pentahydrous for sale.

it doesn't matter for making sts, it's exactly the same just with some water molecules bound into the crystals, but you have to slightly alter the weights you use. if you know molar calculations it's pretty easy to calculate the conversion factor yourself, but if you don't, I still have my enveloppe with calculations laying around here, and the conversion factor I calculated is 1.57 times the weight going from anhydrous to pentahydrous.

Do you get successful reversals everytime? I see both but the anhydrous is sold in bulk i don't need a bulk of it. The pentahydrous i can get a few grams for. So what weight would i need to make a batch of sts with the pentahydrous?

 

[fryge]

I just did it for the first time this year, so I'm still practicing.
so far I have one reversed plant dropping visible pollen that I used to pollinate, but no developing seeds yet(pollinated a few days ago). have some more where the balls haven't grown enough yet, and one that is from the same batch as the first, sts also just starting to wear off, but I haven't noticed visible pollen on her yet. (I had a problem woth those first 2 plants, I probably treated them too strong and too often, and there wasn't any pollen in the balls. now the sts is wearing off, after 2-3 weeks, they're making female flowers again and the balls on that first planted started opening on their own and dropping some pollen. so probably ethylene is needed to ripen the male flowers.)

I used a recipe posted on a lot of forums, but adjusted the amounts a bit to make a smaller amount. I could look up the exact recipe tomorrow(it's late here, 2.48 AM). anyway, I checked that recipe for the molar ratio of 1:4 silver nitrate:sodium thiosulphate and that checked out, just have to look up again what concentration my stock solutions were.
anyway my experience was the mixing was the simple part, the unexpected part were the fully reversed plants with empty balls.

but I'm sure anhydrous vs pentahydrous doesn't matter, it's the same molecule, it just has some water incorporated. but since you're dissolving it in water anyway, that doesn't matter, just the weight is a bit different so you have to use that conversion factor on the recipe.

 

[fryge]

so, the recipe.
still not 100% sure which recipe I used, but I'm pretty sure I used the recipe that's in the STS thread on here, because my calculation-notes I found mention 2,5 grams of sodumthiosuplhgate per 500 ml, and I remember the recipe used equal amounts of stock solutions mixed together(whilke other recipes I found use different amounts of stock solution)
so that recipe is 0,5 grams silver nitrate into 500 ml water+2,5 grams sodiumthiosuplhate in 500 ml water.

silver nitrate is 170 g/mol. so 0,5 grams is 1/340 mol(for concentration per liter x2, since it's ion 500 ml, so 2/340 or 0.00588235294 moles per liter)
sodium thiosulphate(anhydrous) is 158 g/mol. 2.5 grams is 1/63,2 mol, working out to 2/63,2 or 0.03164556962 moles per liter.
0.03164556962/0.00588235294=5.37974683648.
not exactly that 1:4 molar ratio, but close. could be I did use a different recipe, because I remember it worked out pretty close to that 1:4 molar ratio, but maybe in my previous calculations I didn't do it so precisely and just thought it was close enough, or maybe I did adapt the amounts a bit to fit the 1:4 ratio better. anyway, you can use this method to check any recipe for sts you find for that molar ratio(the 1:4 ratio is a ratio I found often mentioned as optimal, since at that ratio pretty much all silver-ions will be in the sts-form, and not as free ions).

for pentahydrous you have to add the weight of 5 water molecules per molecule of sodium thiosulphate, which is 90 g/mol. so the sodium thiosulphate becomes 248 g/mol.
248/158=1,57, so there's that conversion factor.

after mixing you dilute it some more before spraying. I have used up to 1:6 dilution, but that was in the beginning when I was going a little too strong and too frequent in my applications. I now use 1:8 and that reverses just as well as 1:6. the sts seems to stay active for 2-3 weeks, since with that first plant 2 weeks after last application it began forming female flowers again. the other plant took a bit longer, around 3 weeks I think.
so you want to spray around the beginning of flower, to make it differentiate in male balls.
first flowers will be female, don't worry and start applying stronger solution too frequently like I did, just wait and the male flowers will come. around 1-2 weeks after last application you can do another, 2 applications should be sufficient if ou timed it well enough. as soon as you see developing male balls, don't apply anymore so the sts wears off and the male flowers can properly ripen off.

btw, most use a sprayer to apply, but personally I find it more convenient to use a 3 ml pipette to put droplets directly on the buds, but I'm using pretty small plants to reverse, so on large plants with a lot of buds that might be too tedious. but for small plants it's much easier, and you use very little solution.

 

[Proph]

so, the recipe.
still not 100% sure which recipe I used, but I'm pretty sure I used the recipe that's in the STS thread on here, because my calculation-notes I found mention 2,5 grams of sodumthiosuplhgate per 500 ml, and I remember the recipe used equal amounts of stock solutions mixed together(whilke other recipes I found use different amounts of stock solution)
so that recipe is 0,5 grams silver nitrate into 500 ml water+2,5 grams sodiumthiosuplhate in 500 ml water.

silver nitrate is 170 g/mol. so 0,5 grams is 1/340 mol(for concentration per liter x2, since it's ion 500 ml, so 2/340 or 0.00588235294 moles per liter)
sodium thiosulphate(anhydrous) is 158 g/mol. 2.5 grams is 1/63,2 mol, working out to 2/63,2 or 0.03164556962 moles per liter.
0.03164556962/0.00588235294=5.37974683648.
not exactly that 1:4 molar ratio, but close. could be I did use a different recipe, because I remember it worked out pretty close to that 1:4 molar ratio, but maybe in my previous calculations I didn't do it so precisely and just thought it was close enough, or maybe I did adapt the amounts a bit to fit the 1:4 ratio better. anyway, you can use this method to check any recipe for sts you find for that molar ratio(the 1:4 ratio is a ratio I found often mentioned as optimal, since at that ratio pretty much all silver-ions will be in the sts-form, and not as free ions).

for pentahydrous you have to add the weight of 5 water molecules per molecule of sodium thiosulphate, which is 90 g/mol. so the sodium thiosulphate becomes 248 g/mol.
248/158=1,57, so there's that conversion factor.

after mixing you dilute it some more before spraying. I have used up to 1:6 dilution, but that was in the beginning when I was going a little too strong and too frequent in my applications. I now use 1:8 and that reverses just as well as 1:6. the sts seems to stay active for 2-3 weeks, since with that first plant 2 weeks after last application it began forming female flowers again. the other plant took a bit longer, around 3 weeks I think.
so you want to spray around the beginning of flower, to make it differentiate in male balls.
first flowers will be female, don't worry and start applying stronger solution too frequently like I did, just wait and the male flowers will come. around 1-2 weeks after last application you can do another, 2 applications should be sufficient if ou timed it well enough. as soon as you see developing male balls, don't apply anymore so the sts wears off and the male flowers can properly ripen off.

btw, most use a sprayer to apply, but personally I find it more convenient to use a 3 ml pipette to put droplets directly on the buds, but I'm using pretty small plants to reverse, so on large plants with a lot of buds that might be too tedious. but for small plants it's much easier, and you use very little solution.

Thanks for this! Im going to get the ingredients this weekend. So is it still ok to use 2.5g of sodium thiosulfate to 500ml water? Or do I need to recalculate?

 

[seedlingstarter]

So today is 26 days since spraying with cs no sacs yet hoping for some in the next week. I have a new seedling just above ground at a day old thinking about the sts method for that plant. Its a purple kush auto same as the planted trying to be reversed now. The plants are starting to yellow at the lower leave and get tan spots in certain places. I think its due to a mag problem. Fed the last two feelings with Epsom salt and bio bloom. Here are some updated pictures the pistils have all shriveled up with exceptions to the new ones that keep popping up. Calaxys are all swollen. Exactly where do the sacs emerg from? I wish there were more threads with pictures of the transition so I could compare rather than just the pistils shriveling. So the plants in the pic are blue Himalaya and purple kush. The purple kush is of course the purple flowered girl.

 

[fryge]

Thanks for this! Im going to get the ingredients this weekend. So is it still ok to use 2.5g of sodium thiosulfate to 500ml water? Or do I need to recalculate?

recalculate if you're using pentahydrous.
which would work out to a concentration of 1,57*5=7,85 g/l (5 since the 2,5 is for 500 ml, so it's 5 g/l)

as for some pictures of reversal, these are mine:
one of the first reversals, nice full reversal but I treated too strong/frequent resulting in no pollen for a while as mentioned earlier

the other of my first reversals, this one still doesn't give pollen(or I haven't seen it yet)

and this is one of the last batch, that are receiving just 2 treatments with 1:8 dilution(after mixing the sts)(this one didn't reverse fully, just a few balls, but another clone next to it that showed balls a few days later has more balls, still hairs in between. but don't have pictures of that one)

edit:
made a picture of the better reversed clone of the newest batch, so here it is:

 

[fryge]

I just discovered I wrote down the concentration of my sts-stock solution on the back of the lable I put on the bottle of stock solution in my fridge. so now I can check my earlier guesswork.

my lable mentions:
0,25 grams silvernitrate
2 grams sodiumthiosuplhate
in 500 ml water

so indeed pretty much the same what I guessed from my notes and memories, just made the sodiumthiosuplhate into a nice round number. btw, these label-amounts are the final concentration in the mixed but undiluted solution. that's why at first glance it seems half the concentration of the recipe I mentioned earlier, but that earlier mentioned recipe mentions the amounts you weigh for making the stock solutions, but since you then mix equal amounts of both stock solutions, concentration in the final solution becomes half that. you can make the stock solutions different strengths though, if you still end up with those same final concentrations(I think I did that, because I didn't have enough big glasswork available, so I tweaked the stock solutions to fit my available beakers).

 

[seedlingstarter]

Okay guys so the cs route didnt take on the previous plant i was spraying. Dont know if it was the batch i made or if the plant was hard to turn. I dont think i wanna go the cs route any longer. Im thinking of trying the sts method. the sodium thiosulfate i was wondering how much a difference it made between the anhydrous or pentahydrate? Does anyone know cause on ebay the pentahydrate seems to be the only find.

 

[fryge]

for the purpose of making sts, the only difference between anhydrous and pentagydrate is you have to use a little more of the pentahydrate.

it's exactly the same chemical. only the pentahydrate has 5 watermolrecules bound to it(penta=5). since you're dissolving it in water as a step of making sts, it doesn't matter at all wether it has water bound in it before or not.
however, that water that's in there makes it weigh a little more, so you have to add more of the pentahydrate to get the same concentration of the sodiumthiosuplhate in the solution.

when I made my sts I calculated a conversion factor between anhydrous and pentahydrous. from memory, I think it was something like 1.58(so if your recipe is with anhydrous, multiply the weight by 1.58 if you're using pentahydrate).
however, that's from memory, not completely sure I'm remembering the right number. how's your chemistry? if you remember molecular calculations from highschool, you can pretty easily calculate it yourself. just calculate the molecular weight of sodum thiosulphate, then calculate the weight of that+5 watermolecules, and look how they relate.