What do bottled water, pet rocks and “exhaling” co2 bags have in common? You can make them all at home for pennies per pound.

Last winter I got into propagating Blue and Pink Oyster mushrooms while in the planning stages to build a home mushroom propagation enclosure. What I found in my reading was as soon as a mushroom farmer gets their crop to the point of visible production, they have to recirculate the entire volume of their grow room four to six times per hour because of carbon dioxide buildup. Blue and Pink oysters prefer co2 under 600 ppm, the problem is, they constantly secrete it. Pink Oysters in particular are a tropical variety that will actually grow inside a grow room or grow tent provided it stays under 85 farenheit and you shade the fruiting bodies so they dont get tough and crack. As the mushrooms reach maturity they will drop spores so placing the buckets inside a plywood box fitted with a hepa AC filter available anywhere will contain the spore, the gasses will easily circulate through the filter provided your grow room has any air circulation. A simpler alternative is to replace the buckets before they fruit.

You’ll need raw whole oats or raw whole wheat available at farm supply stores in 50lb bags, tap water, a stock pot, some 5 gallon buckets and lids, a 3/4 hole saw, 3/16 or similar drill bit, unscented trash bags and a pink oyster culture.

1) Fill the 5 gal bucket 25% full with whole oats, then add boiling water until 90% full
depending on how big your stock pot is time will vary

2) put the lid on the bucket and burp it daily until it smells like prison wine (3-5 days)

3) drain your oat water off and water your plants with it

4) drill holes in your co2 bucket with the hole saw

5) line the inside of holy bucket with a clear plastic trashbag to create “windows”

6) alternate layers of fermented grain with a sprinkle of mushroom grain spawn

Now quickly lid your mixture, drill a series of vent holes in the top and hot glue a coffee filter over those holes. The more the better as long as all holes are protected by a filter.
put your unused grain spawn in the fridge and consider making a “mother” culture to save money.

If you could see through the bucket youd see all the grain be consumed by a cottony web over the next weeks eventually making a natural styrofoam like brick of lifeform that breathes air, exhales co2 and even gives off heat. You could buy one exhale bag for the same price as a home made 150 gallon 1200 pound exhale bag…or maybe just many smaller ones.

The point is don’t waste your money on the store bought model.

( Or if you already have, those exhaling bags are a self contained mushroom culture, add sterile grain media and its volume will grow up to 10,000x. If you mix in grain and the new grain gets wisps of fiber growing through it, congratulations you cloned your exhaling bags.)

When the bucket “windows” have a white layer behind them and its very firm to the touch, move the buckets away from the marijuana, cut an x in the window and spray with water, this is when the mushroom produces an edible fruiting body. If you don’t like the mushrooms dehydrate them and sell them online, they go for $10-15 per dry ounce…it easily pays for itself if you do the work.

This link shows in detail how its done, with a few differences in technique than i described, just use a heat tolerant mushroom strain like a pink oyster: https://www.youtube.com/watch?v=45b2t7fqhjA

Where I get grain spawn: www.northspore.com

how to master the process: https://fungi.com/collections/books-by-paul-stamets

(images from google)