The main purpose of the terrarium (also called a fruiting chamber or growing chamber) is to provide the steady humidity and temperatures required for mushroom development. Rice cakes will live inside the terrarium during the fruiting phase of the life cycle.
This segment from the dvd let's grow mushrooms! shows one way of making a fruiting chamber. It also describes birthing the mushrooms and a process known as dunk and roll.
Birthing the cakes is simply removing them from the canning jars and cleaning them by washing off any excess material from the surface of the cakes.
The dunk and roll process consists of two parts. Part one, called the dunk, is submerging the cakes in cool water (35-50 degrees F, preferably under 42 degrees F) and keeping them there for 12-24 hours. You can add ice cubes to lower temperature.
This allows the cake to soak in more moisture, which results in a larger harvest. Many experienced growers recommend dunking 24 hours so the cakes absorb more moisture.
Part two, called the roll, is after the cakes have been dunked underwater for 12-24 hours. First they are washed off to remove any material on the surface. Then they are rolled in dry vermiculite.
Rolling them in dry vermiculite causes the vermiculite to cling to the surface of the cakes. The purpose of this is to provide a covering for the cakes which will absorb moisture, which can then hydrate the cakes as needed.
With the dunk and roll process, you can wait until the cakes are 100% colonized, and as soon as they are colonized, birthing them and then performing the dunk and roll.
Another option is to wait until one week after the cakes are 100% colonized (called the consolidation week) and then birthing the cakes, followed by performing the dunk and roll.
The reason for waiting a week is some people find the mushrooms are able to fully colonize the interior of the substrate. They say at the point when the cakes become 100% colonized on the exterior, the interior is not fully colonized.
The fourth segment from the dvd let's grow mushrooms! shows a few types of mushrooms, including Psylocybe cubensis, after they have been in the fruiting chamber for a few days.
There are other options for a fruiting chamber. The first one is a very simple minimal terrarium that works well, but can only handle one rice cake.
The second is based on work done by Psylocybe Fanaticus. It will hold more cakes than the first terrarium, but still requires attention several times a day.
The third or fourth options use the same terrarium as Psylocybe Fanaticus developed but a fish tank air pump and heater, or ultra-sonic humidifier are introduced to keep humidity up. They require very limited maintenance and work very well.
The first terrarium, the Poor Man's Terrarium requires no humidification. It relies on a very small volume of air and the fact the terrarium is sealed very tightly from the outside environment.
All of the last three terrarium setups require the same growing chamber. The difference is the strategy for keeping the humidity high inside of the growing chamber.
If you want, you can start with a simple poor man's terrarium or basic growing chamber version, and see how your first crops turn out. Then you can switch to a better setup later, if you are unhappy with the simple versions.
--- Utility knife (aka razor knife).
--- 2 liter plastic soft drink bottle.
This terrarium is made by cutting a section out of a 2 liter soft drink bottle. This serves two purposes. First, it allows you to put a fully colonized rice cake inside the bottle. The second purpose is it allows the volume of the bottle to be reduced to the point where the moistness of the rice cake can keep it humid.
Remove a section of the bottle using the razor knife. The cut on the lower part of the bottle is not very critical. The top cut is more difficult to do correctly. It needs to be right at the point where the bottle is starting to decrease in diameter.
This is because the top part of the bottle is going to be inserted into the bottom part of the bottle and the two sections need to seal tightly.
The best thing to do is start lower than the diagram indicates and cut small sections off until the top piece of the bottle fits snugly and easily into the bottom section.
Once you locate the correct place to cut for the type of bottle you are using, you can simply cut at the same place and make multiple bottles to handle as many cakes as you wish to fruit at any time.
The cap for the bottle must be screwed on tightly. A damp paper towel can be placed on the bottom of the bottle to help raise the humidity inside the bottle. Twice a day the bottle should be opened to allow new air to be available for the rice cake to consume.
It is best to fan the rice cake to insure new air is surrounding the cake before sealing it back in the bottle. This is the major draw back to this terrarium. If you have a dozen cakes it can become a burden to exchange the air twice a day.
--- Plexiglass (hardware store).
--- Humidity gauge (where to find).
--- Styrofoam cooler (adaptation-11).
--- Silicon glue/caulk (hardware store).
--- Rigid wire mesh, 1/4 or 1/2 inch is ideal (hardware store).
The cooler needs to have a very tight fitting cover. The idea is to seal in humidity, and the looser the lid is, the more difficult this is. Except for the cooler, most things you need can be found at your neighborhood hardware/building supply store.
A humidity gauge with a thermometer is recommended. You will need to be able to check the temperature and humidity throughout the growing process. Available in hardware stores, if not check the housewares section of a department store (adaptation-12).
The plexiglass needs to be large enough to fit inside your terrarium (in this case a cooler). It is best to buy a piece of plexiglass that is a bit larger than what you need and cut it to size with a jigsaw, circular saw, or something that will cut through plexiglass.
Instead of plexiglass, you can use other types of clear rigid plastic (like a fluorescent light diffuser or window insulation). The plexiglass is optional if an ultra sonic humidifier, or fish tank heater and bubblier system to raise humidity (adaptation-13).
Below are diagrams detailing the various components of the terrarium. There is no way to predict the dimensions of the cooler that you will use. You will need to use some common sense as we walk you through the steps to build your terrarium.
The purpose of the rigid wire mesh is to hold the rice cakes off the bottom of the cooler where moisture will collect. The easiest thing to do is cut a piece of wire mesh an inch wider and an inch longer than the dimensions of the bottom of the cooler. Then, use a pair of pliers to bend a 1/2 inch ridge all the way around the piece of wire mesh.
The piece of mesh will be held up by the bent ridge. Often times, when mushrooms are growing, space above them is at a premium. Try not to raise the wire mesh more than a 1/2 inch above the bottom of the cooler. Doing that simply wastes valuable space.
Next, if you are going to use the hand sprayer method of adding humidity, a drip shield needs to be installed. If you are using a fish tank bubblier (air stone) or an ultra sonic humidifier, it is optional but still a good idea. As moisture condenses inside the terrarium, this protects the rice cakes from being 'rained' upon.
Any moisture that forms on the lid of the cooler can drip and will be stopped by the drip shield from hitting the rice cakes. Any moisture that forms on the bottom side of the drip shield will form beads and run down to the side of the terrarium where it can drip harmlessly.
If you use a piece of plexiglass that is textured on one side, put the textured side pointing up. You want a smooth surface on the bottom side of the drip shield so that moisture can easily run down to the side of the terrarium.
The drip shield is held up by several bolts sticking through the side of the cooler. Depending on what size canning jars you use and the height of your wire mesh, you will need to figure out where to put them.
You want the drip shield to be at as steep of angle as possible to make water run down it easily, but you want it high enough that your mushrooms have room to grow without touching the drip shield.
The drip shield needs to fit well. You need a small gap on the edges to let air circulate, but keep it small. About 1/4 inch is good. In other words, the drip shield should fit pretty well to the inside of the cooler, but it is not supposed to be air tight.
Also remember when shaping the drip shield that you can not go to the very top of the cooler because the lid will recess into the cooler a little ways.
If you are using a Styrofoam cooler, you should use washers on the bolts on both the inside and outside of the cooler. This will allow you to tighten the nuts on the bolts snugly.
When tightened snugly, it will keep the bolts from tearing up the soft Styrofoam that the cooler is made from when you move the drip shield during normal maintenance.
Next, the top of the cooler needs to be modified to allow light to enter the terrarium. Psilocybe cubensis is a phototropic mushroom. It needs light to initiate pinning and to tell the mushrooms which way is up.
You should have some plexiglass left over from the drip shield that can be used for this purpose. Cut a hole in the top of cooler. Cut a piece of plexiglass a little bit bigger than the hole in the cooler lid.
Run a bead of silicon glue/caulk all the way around the hole in the cooler top. Position the plexiglass over the hole and let the glue setup. See the following diagram:
That is it, the basic grow chamber (terrarium) is done. There are 3 methods to keep the humidity high and the CO2 concentration low in the grow chamber while the mushrooms are growing. You will need to which method you are going to use.
This is the original method that Psylocybe Fanaticus recommended for the home cultivator to grow mushrooms. It is the least expensive. It is the most labor intensive and forces you to conform to a demanding schedule. The only thing you need in addition to the basic growing chamber is a spray bottle that can put out a fine mist.
The procedure is this: At least four times a day the terrarium needs to have humidity injected into it via the spray bottle. At least twice a day the CO2 that has built up needs to be eliminated. Once a day you need to eliminate water from the bottom of the terrarium that has condensed and formed there.
Once a day, you need to remove the standing water from the bottom of the terrarium. You can use a turkey baster to suck the water out, or you can gently remove each cake and turn the terrarium up side down to drain the water out. If you remove the cakes, be very gentle. Any place you touch the cakes will not fruit. You should pick up the cakes in the same place every time.
Twice a day, the CO2 that has accumulated in the chamber needs to be removed. One method is to remove the drip shield and fan the inside of the cooler with the cover for 10 or 15 seconds. Another method that works well is to have a hair dryer next to the cooler and use it.
Simply lower it into the terrarium with the exhaust jet pointing up and out of the terrarium and turn it on. It will suck all the existing CO2 out of the chamber. Be sure not to hit the rice cakes with the hot exhaust air. It will damage them.
If your hair dryer has a 'cool' setting, use that instead of 'hot'. Incidentally, one cultivator recommends using a vacuum clean instead. He would simply suck the stale air out of the terrarium.
In order to create humidity in the terrarium a spray bottle that is capable of generating a fine mist is used. There are a lot of different products for use in the kitchen that have an adjustable spray nozzle, but if you choose to recycle one of these, make sure it produces a very fine mist.
What ever you use, make sure it is entirely clean of the original chemicals. Let's make this perfectly clear. Make sure the bottle is clean and does not contain anything that will damage the fungus.
The safest thing to do is go to the hardware store and buy a high quality spray bottle. These typically produce a finer mist than most kitchen type spray bottles.
The problem is that you would not be using a spray bottle if you had a little extra cash so we are telling you that you can use a kitchen spray bottle if you are careful.
In order to create the necessary humid environment in the terrarium, the nozzle is slipped under the cover of the cooler and sprayed at the center of the top side of the drip shield. See the following diagram:
After spraying for 5 seconds, pull the spray nozzle out of the cooler and let the lid quickly close, sealing in the vapor. The small water drops will dramatically raise the humidity of the chamber.
The rice cakes can not ever be sprayed directly. The mycelium is very fragile and doing that will damage it. The terrarium needs to be sprayed at least 4 times a day. More is better.
This setup and procedure will work and is very inexpensive, but that is the only good I have to say about it. You become a slave to your terrarium. If you miss a couple sessions, your fungus will most definitely suffer because of it.
Also, you can only support a few growing mushrooms at a time using this procedure. The mushrooms pull a lot of humidity out of the air and this method doesn't provide much excess.
The basic portion of this system was originally pioneered by Psylocybe Fanaticus There are several improvements and adaptations in this section that were not included in the original method.
The idea is to create additional humidity by bubbling air through water. A small fish tank air pump and air stone are used to accomplish this.
This method is inexpensive and allows the terrarium to exist without your constant attention. By itself (without the heater), the major limitation is that depending on how it is implemented, it can only raise the humidity by 10%.
The minimum acceptable amount of humidity needed by the fungus is 85%. If humidity in the room the mushrooms are growing in is going to be less than 70% during the growing cycle, you will have to use the optional submersible fish tank heater, or you will experience problems with this setup.
If you have more than a few mushrooms growing, it is possible this system will fail to keep the humidity high enough by itself. One way to increase the efficiency of this method is a submersible fish tank heater (adaptation-13).
With the use of an air pump, bubblier, and submersible fish tank heater, you can eliminate the need to hand spray the terrarium (without a humidifier). All the materials needed can be obtained at any pet store, or pet department in a department store.
The basic strategy is to place a container of water inside the terrarium and slowly bubble air through the water. If necessary, a hole should be cut in the drip shield so the container can stick up through it.
The top of the container with the water and air stone should be above the drip shield to protect the fungus from water droplets that will get produced. There are several ways the system can be implemented.
Without the heater, the humidity will probably not be raised much more than 10%-15%. With a combination of efficient air pump, air stone with small holes, and submersible fish tank heater, humidity increases of 40% are possible.
The extra benefit to this setup is the fact that air is constantly being exchanged by the air pump, and the home cultivator does not need to eliminate CO2 every day. A small hole can be drilled at the base of the terrarium to let CO2 and water escape.
The hole should be just big enough that water does not bead up and plug the hole. A 3/8 inch hole will accomplish this nicely. Note that a small, snug hole needs to be drilled in the side of the cooler to allow the air line to get inside the cooler.
Most air line is 1/4 inch outside diameter, so a 5/16 inch hole will be the best size. You can not just loop the air line over the side of the cooler and slam the lid on it. You will not get enough humidity if the lid does not fit tightly.
Try this method if using an air pump, bubblier, and submersible fish tank heater do not produce enough humidity. It will effortlessly produce enough humidity to support as many mushrooms as you can grow at once. This setup (like using an air pump) will automatically eliminate CO2 buildup before it occurs.
The drawbacks are the cost, and amount of time it takes to incorporate it into the terrarium. Ultra sonic humidifiers cost around $50 to $100. A little more for a super nice one, a little less for a budget version. A cheap cool mist humidifier can be purchased for about $30, it will work for this.
A warm mist or steam humidifier is not easy to integrate into this terrarium setup. First, the vapor it emits is too hot and will kill the fungus. The second reason is they typically run full blast. They do not have a control to throttle them way back like the ultra sonic humidifiers do.
--- 4 clear 2 liter soft drink bottles.
--- Ultra sonic humidifier (description).
--- 3/8 inch, fine thread bolt.
--- Tube of silicon glue/caulk.
--- 1 dozen 3/8" id grommets.
--- 8 feet vinyl tube 5/16" id, 7/16" od.
First, a small hole needs to be placed in the basic growing chamber to let water and CO2 escape. It should be at the very bottom of the cooler. It needs to be big enough that water will not bead up and plug it. 1/2 to 3/4 of an inch is good.
This setup uses the ultra sonic humidifier to produce air that is close to 100% in humidity. The air flow out of the humidifier is limited by the fact that it has to travel through the 5/16 inch id (inner diameter), 7/16 inch od (outer diameter) vinyl tubing.
That is OK, because we want to limit the amount of air we feed into the terrarium. The humidifier will generate very humid air, with many suspended water particles in it. Any time one of these water particles touches another water drop, they will merge.
We don't want moisture forming on the rice cakes, so limiting the number of suspended water drops we allow into the terrarium is a big step towards this goal. Even so, the air must be dried further (adaptation-21). The air is passed through several stages where it is allowed to swirl and condense.
Each one of these stages is comprised of an empty 2 liter soft drink bottle or some other suitable container. These stages are connected together using the 7/16 inch vinyl tubing.
Every time a piece of vinyl tubing is used, it needs to be fluted. This means it is not cut off square, but rather at a very sharp angle.
This is necessary to help moisture that condenses inside the line to drip out once it reaches the end of the line. Otherwise, it will form a big drop and eventually plug up the line. At that point you have no humidity entering the terrarium.
Drill a 7/16 inch hole in the center of the exhaust lid for the humidifier. Insert a grommet. Apply a bead of silicon glue/caulk to the slit through which vapor normally exits.
You want to plug this slit up. The only exit for vapor should be through a piece of vinyl tubing that will be placed inside this grommet.
Remove the labels on the soft drink bottles. Any large plastic container can be used but the 2 liter soft drink bottles are real nice because the clear ones allow you to see inside (adaptation-24). This is useful to determine if the terrarium is running correctly later. Also, you will be able to see if moisture that has collected in the bottle needs to be emptied out of it.
Heat up the threads on the 3/8 inch bolt using a propane touch or burner on a gas stove. A cigarette lighter will work, but it will take a long time. Hold onto the bolt with the pliers. When the bolt is hot, quickly and neatly poke two holes in each 2 liter soft drink bottle (adaptation-15). See the following diagram for details:
The bolt that is used is deliberately a little smaller than the hole that needs to be generated. The hot bolt will melt the hole a little bit bigger than it is when it pokes through the plastic bottle.
You may need to insert the bolt a second time into the hole and let it touch the sides to expand the diameter of the hole. Some times little chunks of plastic stick to the side of the hole. Use a sharp knife to clean up the edges and insert a grommet.
Check the fit of the vinyl tubing through the grommet. It should be very snug and air tight, but it should not collapse the inner diameter of the tubing very much.
Connect a piece of tubing from the humidifier to the first soft drink bottle. Flute both ends of each piece of vinyl tubing. Connect the this soft drink bottle to the next.
Do this until you have all four soft drink bottles connected. The picture below shows 3 soft drink bottles because that is what is normally required, but for now connect all 4.
Now connect the last soft drink bottle to the terrarium. You will need to poke a hole in the side and insert the tubing. The tubing should be blowing humid air into the part of the terrarium that is above the drip shield.
Fill the humidifier with water and position the various stages of the soft drink bottles between the humidifier and terrarium. At no place should the vinyl tubing have a low spot for condensation to form and plug up the line. Condensation will form in the lines but it should run to the end and drip harmlessly out of the line.
Set the humidity level at the minimum setting. This is still more than you should need (adaptation-19). After you give it time to stabilize, you should see that each stage of the soft drink bottles has less fog in it than the preceding stage.
Usually, 3 bottles is the right amount, but depending on your humidifier and ambient humidity, it could be more or less. You want the last soft drink bottle to just have the slightest hint of fog in it. Add or delete stages as necessary.
The humidity in the terrarium should stabilize at about 90%. The ideal amount of humidity is as much as you can get without moisture forming on the rice cakes. Keep in mind that most humidity meters you get at department stores are not exact, but they will let you know when the humidity is in the 90% range.
The next step in growing magic mushrooms is the growing cycle, which is located in the next section of this guide.
Grow Magic Mushrooms Index
--- Growing Cycle
--- Drying, Preserving
--- Dosage And Ingesting
--- Getting A Spore Syringe
--- Getting Stuff
--- Growing In Bulk
--- List Of Adaptations