Make Your Own Boveda Humidor Bag With Silica Gel Beads

ppm Charlie

Well-Known Member
I am interested in cannabis drying, curing and preservation methods and I found some interesting information on silica gel beads. We have all seen those little pouches inside prescription bottles, vitamin bottles and sometimes packed in with electronic devices. These silica gel pouches are meant to absorb water to keep the contents dry after manufacture and during storage and shipping. Silica gel beads are nontoxic and also used to help preserve certain packaged food items (i.e. dehydrated meals). Silica gel beads not only help dry-out things, they can also be used to help maintain a particular humidity (RH) level in a closed or semi-closed space. For example, museums commonly use silica gel beads to keep a museum exhibit that is sealed or semi-sealed at a certain predetermined RH humidity level for long periods of time. In my deep dive into the subject I found two useful articles.

The first reference talks about how museums use silica gel and the need to maintain humidity at various correct levels in museum exhibits both short and long term. The article also talks about the different kind of silica gels beads that are used in museums, how different types of silica gels are better in certain ranges of humidity and how to mix different silica gels to obtain a fixed humidity (RH level) in a closed (sealed) or semi-closed space (mostly sealed and employee access areas).

The next article I read indicated that a person can make their own silica gel mix that maintains humidity in a closed space in a certain narrow range. For example, the article gives instructions for making a silica gel that maintains 75% RH humidity by simply using silica gel, table salt, water, a plastic bag and a hygrometer. From there, the article gives instruction on how to mix the 75% RH humidity silica gel with "new" (unaltered) silica gel to make silica gel that will maintain humidity in any given range (say, 45%, 55%, 60%, 65% or even 70% RH, etc.).


Silica gel and silica gel beads alone are non-toxic. Silica gel is usually sold in "bead-form" and in colors that tell you when the silica gel is used up (absorbed all the water it can, say originally orange colored but when "used up" yellow colored). Once the silica gel is used up, it can be used again by regenerating it in a heated conventional oven or microwave oven to drive-off the accumulated water. I would stay away from the blue indicator silica gel as it has cobalt-blue in it and cobalt can be harmful to health if ingested in large quantities. However, there are uncolored silica gel beads and also different colored indicator silica gel beads that are nontoxic and safe to use.

Silica gel beads are cheap and easily obtainable in bulk. Boveda Humidor Bags are expensive. Boveda Humidor Bags use various salts for humidity control rather than silica gel. However, silica gel can provide the same humidity control if properly prepared at a fraction of the cost of Boveda Humidor Bags. If a person has a lot of cannabis to preserve it may be cost effective to use silica gel beads for holding humidity at the proper level in closed containers. I would not suggest adding the gel beads directly to the bottom of a container, however, a small cloth pouch or nylon sock could be used to place the silica gel beads in and separate them from your precious dried and cured 420 for short or long-term preservation.

I have not tried to prepare my own silica gel bead humidity control pouches but I plan to and I hope this will decrease my costs of cannabis preservation. If museums can do it, I can do it!

P.S. Preparing the 75% RH silica gel beads described above could also help people calibrate their cheap humidity gauges that go inside their cannabis storage containers since the table salt/water method yields exactly 75% humidity each time. Is my cheap humidity gauge reading correctly? Is it reading high or low, based on the 75% RH silica gel calibration technique?
 

Stunger

Grow Journal of the Month: May 2021, March 2022 - Plant of the Month: May 2021
I don't currently use humidity control pouches myself, but thanks for posting your thoughts around using silica gel alternatives. :thumb:
 

ppm Charlie

Well-Known Member
I am interested in cannabis drying, curing and preservation methods and I found some interesting information on silica gel beads. We have all seen those little pouches inside prescription bottles, vitamin bottles and sometimes packed in with electronic devices. These silica gel pouches are meant to absorb water to keep the contents dry after manufacture and during storage and shipping. Silica gel beads are nontoxic and also used to help preserve certain packaged food items (i.e. dehydrated meals). Silica gel beads not only help dry-out things, they can also be used to help maintain a particular humidity (RH) level in a closed or semi-closed space. For example, museums commonly use silica gel beads to keep a museum exhibit that is sealed or semi-sealed at a certain predetermined RH humidity level for long periods of time. In my deep dive into the subject I found two useful articles.

The first reference talks about how museums use silica gel and the need to maintain humidity at various correct levels in museum exhibits both short and long term. The article also talks about the different kind of silica gels beads that are used in museums, how different types of silica gels are better in certain ranges of humidity and how to mix different silica gels to obtain a fixed humidity (RH level) in a closed (sealed) or semi-closed space (mostly sealed and employee access areas).

The next article I read indicated that a person can make their own silica gel mix that maintains humidity in a closed space in a certain narrow range. For example, the article gives instructions for making a silica gel that maintains 75% RH humidity by simply using silica gel, table salt, water, a plastic bag and a hygrometer. From there, the article gives instruction on how to mix the 75% RH humidity silica gel with "new" (unaltered) silica gel to make silica gel that will maintain humidity in any given range (say, 45%, 55%, 60%, 65% or even 70% RH, etc.).


Silica gel and silica gel beads alone are non-toxic. Silica gel is usually sold in "bead-form" and in colors that tell you when the silica gel is used up (absorbed all the water it can, say originally orange colored but when "used up" yellow colored). Once the silica gel is used up, it can be used again by regenerating it in a heated conventional oven or microwave oven to drive-off the accumulated water. I would stay away from the blue indicator silica gel as it has cobalt-blue in it and cobalt can be harmful to health if ingested in large quantities. However, there are uncolored silica gel beads and also different colored indicator silica gel beads that are nontoxic and safe to use.

Silica gel beads are cheap and easily obtainable in bulk. Boveda Humidor Bags are expensive. Boveda Humidor Bags use various salts for humidity control rather than silica gel. However, silica gel can provide the same humidity control if properly prepared at a fraction of the cost of Boveda Humidor Bags. If a person has a lot of cannabis to preserve it may be cost effective to use silica gel beads for holding humidity at the proper level in closed containers. I would not suggest adding the gel beads directly to the bottom of a container, however, a small cloth pouch or nylon sock could be used to place the silica gel beads in and separate them from your precious dried and cured 420 for short or long-term preservation.

I have not tried to prepare my own silica gel bead humidity control pouches but I plan to and I hope this will decrease my costs of cannabis preservation. If museums can do it, I can do it!

P.S. Preparing the 75% RH silica gel beads described above could also help people calibrate their cheap humidity gauges that go inside their cannabis storage containers since the table salt/water method yields exactly 75% humidity each time. Is my cheap humidity gauge reading correctly? Is it reading high or low, based on the 75% RH silica gel calibration technique?
Apologies. The first article regarding museum use of silica gel could not be posted because it is a .pdf.
 

Morda Grown

Well-Known Member
Here is a thought, How about using coffee filters or bulk empty (make your own) tea bags to hold the silica. They are breathable and easy to get not to mention very cheap.
 

ppm Charlie

Well-Known Member
Here is a thought, How about using coffee filters or bulk empty (make your own) tea bags to hold the silica. They are breathable and easy to get not to mention very cheap.
Great thought! Thank you for your helpful and valuable input. I will try it.
 

ppm Charlie

Well-Known Member
I was also thinking of other ways to use silica gel. I thought that it may be useful to help extract moisture from cannabis for those that use the "low and slow" refrigerator technique for drying cannabis. If a tray of silica gel beads enclosed in tea bags or coffee filters was placed in the refrigerator with the cannabis it may help extract the initial moisture surge, be less stressful for the refrigerator regarding moisture control, help shorten the time for required drying and help achieve the final "target" RH for the drying cannabis. The silica gel trays would have to be changed out regularly and reactivated but this technique may aid those using the refrigerator drying "low and slow" technique.
 

Bob Loblaw

Well-Known Member
Hmmm? I'm not the sharpest tool in the shed but...
Seems to me the secret to the Boveda pack is that it regulates to a certain % moisture. Silica beads do not regulate they absorb.
I don't know if it's the guts (salts) or the packaging but Boveda packs do both humidify or dehumidify depending on the current moisture level. At least that was my understanding of the product.

5 months ago I recharged a few of my Boveda, I put them in a damp environment until the salts turned to water, then I put them in one of my jars. I just checked and they are still jelly like.
They work both ways.
 

Morda Grown

Well-Known Member
I'm thinking that silica could help more in the drying process than the curing and storage. @Bob Loblaw makes a good point.
 

ppm Charlie

Well-Known Member
Hmmm? I'm not the sharpest tool in the shed but...
Seems to me the secret to the Boveda pack is that it regulates to a certain % moisture. Silica beads do not regulate they absorb.
I don't know if it's the guts (salts) or the packaging but Boveda packs do both humidify or dehumidify depending on the current moisture level. At least that was my understanding of the product.

5 months ago I recharged a few of my Boveda, I put them in a damp environment until the salts turned to water, then I put them in one of my jars. I just checked and they are still jelly like.
They work both ways.
I believe you misunderstand the properties of silica gels. Museums and industrial manufacturing facilities use silica gel all the time to maintain a humidity at any level they want (long term or short term) by mixing different types of silica gels and conditioning those gels to properly "buffer" RH humidity level. Conditioned silica gels can maintain the humidity at a certain RH in a closed or semi-closed environment.

You are correct that silica gel absorbs moisture. Silica gels can also "give back" or desorb moisture. The following article gives instruction in this technique and provides procedures and equations for mixing and conditioning a silica gel to maintain a buffered RH level.

Silica Gel: Passive Control of Relative Humidity – Technical Bulletin 33 - Canada.ca

I encourage you to read the citation I posted earlier in this thread. I have re-posted it above.

I quote from the article regarding using conditioned silica gel for RH buffering in museum enclosures:

"In practice, as water vapour infiltrates or exfiltrates from an enclosure, the sorbent will minimize the change in RH by absorbing or desorbing the water."

Boveda paks do the same thing...they absorb and desorb water from the salts in the bag, however, as you found, Boveda packs cannot be easily reused. Silica gels are better because they can be reused many times over by heating them in an oven and rejuvenating them (driving off moisture absorbed). The rejuvenated silica gel would have to be re-conditioned for buffering of RH to the proper level again, however, silica gel is reusable. Boveda packs, not so much. I doubt the manufacturer of Boveda packs has any interest in rejuvenation of their product because if they did, they would not sell as much product.

Thank you for your input. I enjoy discussing and interacting in the community very much.
 

ppm Charlie

Well-Known Member
I'm thinking that silica could help more in the drying process than the curing and storage. @Bob Loblaw makes a good point.
Please read the article I cited, I am sure you will change your mind. Thank you for your input.
 

ppm Charlie

Well-Known Member
Try cutting open a new or used Boveda pack. You will find a mixture of mineral salts (and possibly silica gel too). The Boveda outer packaging has nothing to do with humidity regulation, it is simply the enclosure used to contain the salts and a packaging porous enough to allow water vapor to pass freely in-and-out. Maintaining moisture percentage in air, an object or buffer is all about maintaining proper RH in a closed or semi-closed environment or pouch, or sealed glass jar, or grow tent, or grow room, etc.
 

Morda Grown

Well-Known Member
Please read the article I cited, I am sure you will change your mind. Thank you for your input.

Yes I will give it a read I'm interested in it and have just not taken the time. I do use silica in my on-hand bud jar without any over drying issue. I think it has a use for sure. Didn't you say it is level at 75%? If I'm reading that right, then it wouldn't it be a little high for curing....
 

ppm Charlie

Well-Known Member
Yes I will give it a read I'm interested in it and have just not taken the time. I do use silica in my on-hand bud jar without any over drying issue. I think it has a use for sure. Didn't you say it is level at 75%? If I'm reading that right, then it wouldn't it be a little high for curing....
There are several types of silica gel the article describes. Some are best for low humidity, say 2-10% RH (just an example). Then there are silica gels that are better for mid-humidity, say 50% to 80% RH and one for high humidity, say 80%+ RH. What the article describes is taking a mid-humidity silica gel and conditioning it to buffer at 75% RH. Then it gives an equation for mixing in a lower humidity silica gel to lower that buffered RH silica gel to the mid-range, say 55%, 60%, 65%...whatever is required. Since you have worked with silica gel in the past, you recognize that once they absorb all the moisture possible, the RH levels off and basically remains fixed. This is the point of the article...you adjust the mixture of silica gel and condition it so that it resists changes in RH either higher or lower.
 

Morda Grown

Well-Known Member
This may be a better option... Art Sorb Beads. You can find them at Talas, the first supplier in the link you posted.

"Art Sorb is a pre-conditioned silica gel that has a unique ability to both absorb and release atmospheric moisture in order to maintain a pre-set relative humidity within a sealed environment. Available in 40%, 50% and 60% relative humidity. It is capable of absorbing up to 5 times us much moisture as regular density silica."
 

ppm Charlie

Well-Known Member
This may be a better option... Art Sorb Beads. You can find them at Talas, the first supplier in the link you posted.

"Art Sorb is a pre-conditioned silica gel that has a unique ability to both absorb and release atmospheric moisture in order to maintain a pre-set relative humidity within a sealed environment. Available in 40%, 50% and 60% relative humidity. It is capable of absorbing up to 5 times us much moisture as regular density silica."
Thank you! Maybe I won't have to mix my own. If it is cheaper the Boveda packs...I am in! I learn something everyday. Your input is most valuable and timely.
 

Morda Grown

Well-Known Member
Thank you! Maybe I won't have to mix my own. If it is cheaper the Boveda packs...I am in! I learn something everyday. Your input is most valuable and timely.
They have it in bulk at the site, that way you can still bag your own. :)
 

ppm Charlie

Well-Known Member
This may be a better option... Art Sorb Beads. You can find them at Talas, the first supplier in the link you posted.

"Art Sorb is a pre-conditioned silica gel that has a unique ability to both absorb and release atmospheric moisture in order to maintain a pre-set relative humidity within a sealed environment. Available in 40%, 50% and 60% relative humidity. It is capable of absorbing up to 5 times us much moisture as regular density silica."
A pound of Art Sorb Beads at 60% put in tea bags or coffee filters would last a long time and go inside many, many preservation jars. A little goes a long way. Thank you for your time and input.
 
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