5 Simple Steps On How To Build an (SGFC) Shotgun Fruiting Chamber

Mushrooms are picky; that sounds cheeky, right? Unfortunately, that's the case. As much as we enjoy picking mushrooms, we won't have anything to pick if we don't provide the ideal environment for mushrooms to thrive.

If you want to provide the right balance of humidity and fresh air so the mushroom can thrive, you need to build an SGFC. A fruiting shotgun chamber is an easy you to achieve this.

What is an SGFC?

In a simple term, you can say that the fruiting shotgun chamber is a good-sized tote with holes all over them and a few inches of damp perlite under them.

The damp pearlite serves as a humidifier that helps maintain humidity. The holes give room for the exchange of fresh air and similar necessary gasses. To have enough natural light reaching your mushroom, make sure the tote is clear.

The holes over the whole body of the tote inspired the name "Shotgun fruiting chamber."

What is Perlite?

Perlite is a natural volcanic mineral. When perlite expands, it forms a porous and coarse granule with a large surface area. The perlite granules can retain water. This water takes time to evaporate. This evaporation is the reason for the high humidity in the fruiting chamber.

Building an SGFC

Building a shotgun fruiting chamber doesn't take long; all you need are just a few essential tools. If all the materials you need are available, it won't take an hour to build your SGFC. 

Materials you need

  • A transparent plastic tote (70 QT)
  • Coarse perlite (10-12 QT)
  • A spray bottle
  • Hygrometer (not compulsory)

Tools you need

  • A 1/4”bit power drill
  • Sharp marker
  • Measuring tape

Step 1: Mark out holes on the tote

To ensure there's sufficient fresh air exchange through the SGFC, you should make holes of even diameter on all sides of the tote. You can use your marker to mark out the holes. Ensure that the spacing between the holes is equal.

Step 2: Bore the holes.

Using a 1/4"bit power drill on the tote, bore all the holes you've marked out using your marker. Don't apply too much force so that the tote will not crack. After drilling through the tote, ensure you trim them, so plastic shards don't remain on the edges. It may be repetitive, but it doesn't require ample time.

Step 3: Fill the bottom of the tote with perlite

Load some inches of perlite into the bottom of your SGFC.the quantity doesn't matter; ensure you cover the bottom of the tote completely.

If you have a tote with a very smooth bottom, you must employ coarse perlite. Fine perlite could fall out through the holes in your bore, but coarse perlite wouldn't. Also, fine perlite particles can't retain water as much as coarse perlite will.

Step 4: Soak perlite

The next phase is to soak your perlite. Pour water on the dry perlite you’ve already poured at the bottom of your SGFC. Ensure to mix the water and perlite until the coarse is well moist. Your goal is to have your perlite moist so it can evaporate with time while keeping your SGFC humid.

Step 5: Arrange your fruiting block in the fruiting chamber

If you carry out the previous 4 steps correctly, you would have a relatively humid environment. You will also have a chamber that allows the adequate exchange of fresh air and similar gasses.

You can employ the use of mushroom grow kits, supplemented sawdust fruiting blocks, or the usual technique applied when using an SGFC "PF technique."

As much as it is not necessary, you can use a hygrometer. You can position it in your fruiting chamber so you can monitor the humidity of your SGFC. That way, you will know if spaying your chamber is necessary or not. As time passes, you will learn what humidity levels suit all the different stages of the fruiting cycle.

Guide to using shotgun fruiting chamber

The shotgun fruiting chamber doesn't require much maintenance, but you do some things when using them.

Fan and spray

The holes on the body of your tote allow the exchange of fresh air, but often time it is not enough. When you arrange your fruiting blocks inside the fruiting chamber, uncover them and fan them at least once or twice a day.

Try as much as possible to mist your chamber after fanning; that way, you get to maintain the humidity. You can achieve this by using a spray bottle and spraying enough water to soak the perlite at the bottom of the SGFC.

Ensure you don’t spray the fruiting blocks when spraying the SGFC. Spraying the mycelium or the mushroom fruit body with water can bring about bacterial blotch.

Use a Hygrometer

You use the hygrometer to monitor the humidity in your fruiting chamber. It is not a necessity, but it helps. With a hygrometer, you know how well the fruiting environment is kept moist.

Typically, you will want to maintain around 70-90% humidity level. If the humidity drops significantly, the result will be affected. Worst case, your mushrooms wouldn't fruit at all; the best case you get small fruit with lots of cracks.

Either digital or analog, any type of hygrometer you use works fine. Just be sure it can measure humidity as high as 90%, and you are good. Some hygrometers can accurately measure very high humidity levels, especially the types used in humidors. Using one of that ilk will be perfect.

Provide light for your fruiting chamber

It's a big misconception that mushrooms need a dark environment to fruit well. Some do, but most mushrooms require considerable light to fruit well.

Ensure that the light you provide for the fruiting chamber is a natural but indirect source of sunlight. Direct sunlight is not an option for you; it can heat the SGFC, causing you to lose the humidity you've done so much to maintain.

Indirect sunlight is your best bet; close to a window that doesn't have issues with sun rays works just fine. If you don't have a source of indirect sunlight, you can supplement it with artificial light.

Florescent light works well; 12 hours on and the other 12 off can make up for the natural light cycle. Using fluorescent light ensures ample distance from the fruiting blocks, so it doesn't heat them. Which will lead to overheating of the whole chamber.

An easy and reliable solution

When it comes to building a fruiting chamber, many are using automated humidifiers and fans with a lot of space. But you can never go wrong starting out using SGFC.

As much as they are easy to build, they are also easy solutions for providing perfect conditions for your mushrooms to thrive. If you want to try out something with little or no risk in growing mushrooms, then using the SGFC is your best option.

The statements from this article are critical and valuable, but they have not been evaluated by the FDA. Don't see this information as an avenue to self-medicate and ignore proper consultation with your physician. Our products are not meant to be used for preventing, treating, or diagnosing any kind of ill-health.


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