I bought some Silver Nitrate and Sodium Thiosulphate back in 2019 to reverse a plant I had. I have a couple going now that I’d like to reverse also. When I went to make the STS for them I noticed both the Silver Nitrate and Sodium Thiosulphate were solidifying in the bottles. I’ve kept them both in my house on a shelf and lids on tight. I was able to break them up enough to make the mixture but I’m wondering if anyone else has had this issue and how it turned out for you. I should just order some new chemicals, but don’t really want to if I can still use what I have. Anyone had this happen and have success with it?
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@Sebring would prolly be the one to ask.
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Let’s see if he weighs in. Thanks!!
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Having the chemicals “clump” is likely a sign of settling and or moisture. I just received a brand new shipment of STS dry chem from a lab supplier (The Science Company) and the Sodium Thiosulfate was a bit clumped.
It is essential that the dry chem is cold stored for active shelf life reasons. You may still be able to make STS and block ethylene production if the chemicals are active enough to make STS but I would suggest refrigerating what you have left in case it is still good.
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I made a batch of STS and will be spraying a couple of clones tomorrow. I’ll throw the chemicals in the fridge and see if this still works. If not I’ll order more and keep them sealed in the fridge. Thanks for the help!
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The dry chemicals are just fine if they’ve absorbed a little moisture and clumped up. They’d be good for years.
It’s the STS itself that needs refrigeration once all mixed up. The Part A & B soln’s will keep for a long time too if kept separate and in a cool, dark place.
You can buy STS ready to spray and who knows how long it’s been sitting in who knows what conditions. Who knows if it still works either. lol
Don’t worry about the dry stuff tho you may want to use 10% more or so to compensate for the added weight of the moisture.
I got a 500g can of the sodium thio anhydrous last year and keep the can sealed with tape so no moisture gets in. I made my 12g of silver nitrate and it’s just fine sitting in a small vial minus what I’ve used and shipped out to a few people. No clumping yet and still snowy white.
My first try at spraying a couple branches on two plants didn’t get me balls or pollen. I started spraying at 3 weeks flower but will try from the flip next time to see if that works. I’ll spray a whole small plant tho too. I have an Earth Lover from Sebring that looks to be all CBD that I’ll get some clones off to experiment with. Was supposed to be a fem auto but grew as a fem regular and got huge outside last summer. Huge for me at least. 
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the mix of the two chemicals is good for one grow.
if you have left overs of a mix and b mix separate they are only good for 4 months although i read 6 months, i found out the hard way and the two when mixed together at 4 months was no longer what it should have been.
the dry chemicals are good for as long as you keep them dry.
last thing i learned was always start with a fresh mix and dispose of any left overs. easy to mix and stuff is cheap
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