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STS recipe ; Sodium thiosulfate -pentahydrate- test? ; dosage

NEED 4 SEED

Well-known member
Ok so I've stumbled across this different recipe for STS treatment:

https://www.sigmaaldrich.com/technical-documents/protocols/biology/silver-thiosulfate.html

Someone at Strainhunters forum posted it with added quantities for the pentahydrate version of sodium thiosulfate.

https://forums.strainhunters.com/to...own-sts-feminization-mixture-for-a-few-bucks/

Now, I have bought the salt from a private person and it had no label on it. Is there a way to check whether I have the pure or the pentahydrate version?
I have read the pentahydrate is the one they use as fixing salt, so chances are that I got this one. It worked for one experiment in the past but later on with different plants they didn't transform completely. I may have to buy a labelled product but wanted to know if I could use what I have before getting rid of it.

The person on Strainhunters is giving no word about the frequency or timing of application but states that it can be diluted for a working solution. Some other guy at instagram says he uses it undiluted but giving advice to use it only 2 times, once 2 weeks before 12:12 and again 2 weeks after 12:12.
Is someone else here using this main recipe with success and can talk about timing and dosage?
 
That Sigma recipe has been available on the net for quite a few years now and many others have quoted it on the forums. It is an unsuitable recipe without modification as the quantities used are impractical. After making up the working solution you are left with 80ml of Silver nitrate stock solution and 20ml of Sodium thiosulfate stock solution, so therefore you cannot make more without making new stock solutions. Also, it doesn't account for the use of Sodium thiosulfate pentahydrate and mentions nothing about appropriate dilutions or usage frequencies.

I'm not sure which recipe you are using (Sigma's or Strainhunter) but I would be aiming for around 0.2mg Silver nitrate/ml in the working solution, and spraying once a week starting at the beginning of 12/12.

I usually only spray one branch and only spray the tips, avoiding the leaves if possible.

Cheers

.
 
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B

beanz

spraying once a week starting at the beginning of 12/12.

Cheers


.
you don,t spray once a week .
you spray once then a second application week later ( thats all ). my experience is once is enough people need to be patient .

I,m not going to spread bs round the internet with figures as I,ve got them written on my bottles , hammer realised there is two different types of thiosulfate also one requires more than another.

theres a search function and several threads to read more about it
 

djonkoman

Active member
Veteran
I'm not sure which recipe you are using (Sigma's or Strainhunter) but I would be aiming for around 0.2mg Silver nitrate/ml in the working solution, and spraying once a week starting at the beginning of 12/12.

nice to see some concentrations mentioned that others use.
just calculated back from the recipe I used, and my working solution is between 0.1 and 0.05 mg silver nitrate/ml(don't remember from which forum I got the original recipe, but I adapted it a bit and wrote down the amounts on the bottle, and it says 0.25 grams silver nitrate in 500 ml water, which I've used in different dilutions from 1:5 to 1:10)

if I remember right, I arived at a conversion factor of 1.58 between the weight of sodium thiosulphate and the pentahydrate(but I'm remembering this, not have it written down, so you'd need to check yourself if that 1.58 is right)
 
you don,t spray once a week .
you spray once then a second application week later ( thats all ).
What you are suggesting is still once a week for two weeks. I just didn't put a time limit on it as I do it as required, and use a relatively dilute solution of 0.2mg of AgNo4/ml. I have seen some recipes with as much as 3.4mg/ml, which is 17 times stronger.

The conversion from Sodium thiosulfate to pentahydrate is multiply the amount by 1.57
 
B

beanz

What you are suggesting is still once a week for two weeks. I just didn't put a time limit on it as I do it as required, and use a relatively dilute solution of 0.2mg of AgNo4/ml. I have seen some recipes with as much as 3.4mg/ml, which is 17 times stronger.

The conversion from Sodium thiosulfate to pentahydrate is multiply the amount by 1.57

no I actually suggested once was enough , people need patience !!

most say two is required .....but if you did a application following week you wouldn't know if ones required anyway . thats what people say so thats what they do .

or then someone reads a post that isn't clear and sprays every week and kills the plant

but what do I know anyway ,
 
no I actually suggested once was enough , people need patience !!

most say two is required .....but if you did a application following week you wouldn't know if ones required anyway . thats what people say so thats what they do .

or then someone reads a post that isn't clear and sprays every week and kills the plant

but what do I know anyway ,
I get you and I understand that once can be enough. I have seen good results with a low concentration sprayed several times and the plant showed minimal ill effects. I usually only spray one branch and only spray the tips, avoiding the leaves.
 

Douglas.Curtis

Autistic Diplomat in Training
Here's a working recipe. Spray every 5 days to get pure male results like the photo. Link As you can see, the plant stays super healthy.

The recipe makes more than a pint, so be aware.

No clue how to check your specific powder, sorry.
 

Blowmonkey

Active member
Pentahydrate are colourless crystals, anhydrous is a white powder. Sigma has the anhydrous formula iirc, if you have pentahydrate you need to multiply the amount of thiosulfate with 0.64.

There's all kinds of formula's on the internet, I went with the one I'd seen here years ago. That one left me with way too much sts stock material though, so I downsized the amounts a little. 50 mg of silver nitrate in 50 ml of water, 250 mg of thiosulfate in 50 ml of water, stir both till everything is dissolved, mix the two solutions, stir again, then add 900 ml of water to have a 1 in 9 stock solution. Use less water if you want a hotter solution. Even this stuff can be stored in the fridge for a long time without any noticeable deterioration, I'm talking about at least a year or more.

Definitely use demineralised water for everything, no tap, not even for the thiosulfate solution. Also never use more silver nitrate than necessary, you'd rather put in a little more thiosulfate instead of silver nitrate, this way you're sure all the silver nitrate has reacted with the thiosulfate.

The reason noone is giving any precise amounts or frequencies is because it really is strain dependent, amongst other things. Start spraying your female before you flip to 12/12, move it into flower shortly after. Some need almost weekly applications till they start reversing and dropping pollen, some are happy with less. The more you need to spray it and the harder it is to reverse, the better imo. To me it's simply another indicator the mother is hard(er) to stress into intersex regularly.
 
B

beanz

how do you know if some need weekly applications and some less ? please explain that too me ? the only thing you could go by if if its not showing balls ...thing is that could be several sprays in if thats the indicator lol

anyway my experience is I reversed indica , poly hybrids , sativa hybrids , and full blood sativa with one spray .
the only thing that took longer was a biker Kush it didn't need a ""extra spray " just took longer .

anyway I shared my experience ,
 
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NEED 4 SEED

Well-known member
Here's a working recipe. Spray every 5 days to get pure male results like the photo. Link As you can see, the plant stays super healthy.

The recipe makes more than a pint, so be aware.

No clue how to check your specific powder, sorry.

That was the recipe I was using last time and it failed but I may have had the pentahydrate. The anhydrous one is ordered and I will do another test with that.

My first reversal, which worked pretty well, was in 2014 where I reverted an Agent Orange lady by using this recipe: https://www.icmag.com/ic/showthread.php?t=199540. Studying my notes from back then I realized I have later changed the frequency to once a week, I don't know why, maybe I got into "the more, the better" feeling. I actually succeeded back then by applying a first spray on day 1 of 12:12 and a second spray the following day and then doing nothing for 22 days. The first pollen sacs became visible 16 days later. Another week later I sprayed a 3rd time and 5 days later the first pollen flew. So this recipe worked (with probably the pentahydrate) and didn't work when I increased the frequency of application. I am learning from that, I will have the anhydrous version and will only spray twice or so.
 

NEED 4 SEED

Well-known member
Pentahydrate are colourless crystals, anhydrous is a white powder. Sigma has the anhydrous formula iirc, if you have pentahydrate you need to multiply the amount of thiosulfate with 0.64.

Mine are pretty big crystals, looks like coarse salt or quartz.

There's all kinds of formula's on the internet, I went with the one I'd seen here years ago. That one left me with way too much sts stock material though, so I downsized the amounts a little. 50 mg of silver nitrate in 50 ml of water, 250 mg of thiosulfate in 50 ml of water, stir both till everything is dissolved, mix the two solutions, stir again, then add 900 ml of water to have a 1 in 9 stock solution. Use less water if you want a hotter solution. Even this stuff can be stored in the fridge for a long time without any noticeable deterioration, I'm talking about at least a year or more.

That's the "classic" formula.

Definitely use demineralised water for everything, no tap, not even for the thiosulfate solution. Also never use more silver nitrate than necessary, you'd rather put in a little more thiosulfate instead of silver nitrate, this way you're sure all the silver nitrate has reacted with the thiosulfate.

Good points (I guess).
 

Douglas.Curtis

Autistic Diplomat in Training
Cannabis is the only plant I've seen where the recommendation is one or two sprays. The rest of the horticultural world sprays every 5'ish days. If my plants show stress I would dilute and keep going.

Just an fyi...
 

Blowmonkey

Active member
how do you know if some need weekly applications and some less ? please explain that too me ? the only thing you could go by if if its not showing balls ...thing is that could be several sprays in if thats the indicator lol

You know, this irks me, because you might be right. Might be, as I have played around with sts a fair bit, but it's not like I've run double blinds and can convince you or myself with any concrete evidence, it's mostly experience, forum posts and science articles which I and everyone else have been basing their methods on. But yeah, let's run a double blind with some numbers. Any suggestions as to concentrations and numbers of plants you'd like to see?

I had a lengthy reply about how we should not consider cannabis dioecious, rather subdioecious, how you cannot gauge how a plant behaves after only one or two grows and especially not outside, how easy it is to reverse has some bearing on it's true sexuality, but none of that matters since it's all conjecture anyways.

The fact that I haven't seen any banana's or balls in over 7 years in different environments on the plants that I find harder to reverse might have no relation with it's dioeciousness, but I feel it does. Still, I'd like to see some confirmation myself as well.
 

brickweeder

Well-known member
Tried the strainhunters recipe a few days ago, but only diluted the mixed product 1:2, and that burned some of the lower leaves, so it is better to dilute at least 1:3 after mixing A & B.
 

Elmer Bud

Genotype Sex Worker AKA strain whore
Veteran
no I actually suggested once was enough , people need patience !!

most say two is required .....but if you did a application following week you wouldn't know if ones required anyway . thats what people say so thats what they do .

or then someone reads a post that isn't clear and sprays every week and kills the plant

but what do I know anyway ,


G `day B

I read the paper by Moham Ram that this tech comes from .
They found too much silver actually inhibits pollen .

So maybe some of the old stories about this cut or that can`t be reversed is because like you say people are impatient .

I investigated some fem spray at the Hydro store . Active ingredient gibberilic acid ?

Thanks for sharin

EB .
 
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