Make a sealed unit bubbler with forced air humidifier that is beautiful and effective
Makin Deh Bitchen Bubbleh By Teh Honeypotty
A lot of people recommend making humidifiers by adapting commercial humidifier units for shroom growing. It's actually much harder to make a good shroom humidifier out of a room humidifier than it is to build one from scratch! And, the scratch-built system can do things that a normal room humidifier can't - like disinfect the air and act as an air-lock/positive pressure system. The total cost of the bitchen bubbleh was about $30 - my entire "fine art" terrarium complex weighed in at a whopping $60 or so. Since the whole system is connected this paper will describe the entire terrarium complex - but you're welcome to build just the bubbleh.
The only thing I ask is that this bubbleh design remain open and free. Please do not use this design to offer a bubbleh for sale. Don't make money off my design, or you suck and I will haunt you from the grave!
The bubbleh works by using an ultrasonic mister to atomize water, which is in a tall container under mild pressure. The height of the container is important, since the damper mist will tend to be heavier, and will sink to the bottom of the container. A tube in the top of the container carries moist air to the terrarium. To make the air move, mild pressure is provided by a fishtank air pump, which uses the bubbleh's water supply as an air-lock. Because the mist tends to remain in the pressure container, the bubbleh does not waste a lot of water - a typical 2-week growing cycle can all run from a single fill of water.
Unlike with a conventional humidifier, there is no need to worry about too much air-flow, or too much moisture - the small amount of air pushed by the fishtank air pump is just enough to keep things moving and to make a cool bubbling sound. Typically, I put about 3" of distilled water in the bottom of the bubbleh and that's sufficient to keep it humidifying a fishtank-sized terrarium for several weeks. Since the bubbleh's container is closed, you're not going to risk infecting everything by having to open things up to add water all the time. You can scale this system easily, by using an air pump that carries more air, based on the size of your terrarium. If you're concerned about infection getting injected through the air supply, you can add a disinfectant air lock unit - maybe just because it looks cool.
Another design feature of teh bubbleh that I really like is it's pretty fire-safe. I don't like the idea of running room humidifiers in ultra-wet environments; that's just asking for a short-circuit. Teh bubbleh is not likely to catch fire or wear out - it's good design from a failure standpoint.
You will need
A container to act as the pressure chamber, with lid
An ultrasonic mister
A 1/2" hose barb
A piece of 1/2" vinyl hose
An aquarium air-hose hose barb
An aquarium air pump
Aquarium hose clips and suction cups
A drill and some bits
Low to moderate intelligence
Just in case you don't know what a hose barb is, it's one of those finned hose-connectors that you can stick a hose into from either side. For the aquarium hoses you can get a pack of barbs for $0.99 and for the 1/2" hose you can find them at any hardware store. Use a plastic barb, unless you're going totally steampunk. Can you picture a steampunk bubbleh with a stainless containment and a window showing the steam, with big brass valves and gauges and stainless braided hoses? Of course you can!
The easiest place to get the ultrasonic mister is on Ebay or at WAL-MART "after halloween" sale. Expect to pay between $10 and $30, depending on how clever you are. Because I am the ultra-cool guy, I got the ultrasonic mister that came with a free skull for $10 at WAL-MART:
The aquarium pump and other stuff is self-explanatory.
For the pressure container, I like the 1/2 gallon plastic food jars that they sell at WAL-MART. The plastic jars are attractive, cheap, and very tough - made of clear PETN, which shows the neat-o fog very nicely. It's also easy for silicone glue to stick to the plastic. The container you use should have a decent lid which closes tightly. Plastic will make your life easier here. I made a bubbleh for a friend using a glass-stoppered apothecary flask that I had to drill with a diamond bit. Don't do that. That's a pain in the ass.
Drill two holes in the lid. One should be large enough for the 1/2" barb, and the other for the fishtank hose barb. Make the large on one side of the lid, with the smaller one off to the side. Be sure that the barbs sticking through the lid won't interfere with the lid closing. I.e.; don't put them all the way over against the edge. Cut the bottom off the 1/2" barb so that enough will stick through the lid for the glue to hold, but so it doesn't protrude far into the container. Glue the barbs in with silicone glue.
Glue 2 or 3 of the suction cup aquarium hose mounts down the side of the container, with the lowest one fairly near the bottom.
Drill a hole in the upper part of the container for the ultrasonic mister's power wire. The mister I got came with a very convenient grommet for the power, so I just drilled the hole the correct size, and inserted the grommet with a bit of silicone glue to lubricate it and make it seal perfectly.
To mount the ultrasonic mister on the bottom of the container I used 2 pieces of industrial velcro (I have a lot lying around). If you don't feel like being artistic, you can just glue the mister down with silicone. The misters have a 5000 hour lifespan so you're not going to be replacing them very often.
Once the glue holding the suction cups and barbs has dried, mount a piece of fishtank hose along the side so that the end of the hose will be below the water level. The other end of the hose goes up to the lid and connects to the fishtank hose barb. Make sure there's enough slack that you'll be able to take the lid off - about 10" - it'll just coil inside. Mount the 1/2" hose on 1/2" barb on the top of the lid, and connect the other end of the fishtank hose barb to a hose leading to the aquarium air pump.
To disinfect the bubbleh take a cup of water and some bleach and pour it down the 1/2" tube with a funnel. Shake it around, then hold it upside down so it drains out, and rinse it with a couple passes of distilled water. Keep from opening the lid while you're doing this and your bubbleh will be a sanctified environment! Then funnel enough distilled water down the hose that the ultrasonic unit has about 2" of water above it. Now you're loaded and ready to go!
Make sure that the in-hose from the aquarium pump is under the water; this makes the water serve as an air-lock that will force the moist air up the 1/2" hose at the top. Because of the curvature of the hose and the fact that the container is tall, the air that gets up the hose will be extremely moist but will not be wet. The 1/2" hose connects to your terrarium.
In action, the bubbleh makes a pleasant sound and looks extremely bad-ass with all the fog and the crazy LEDs.
The terrarium is set up with a water bath on the bottom and a grill to put cakes on. I let the cakes sit for a couple of days and then roll them in vermiculite, wrap them in aluminum foil, and put a layer of vermiculite on the open top. There is a fishtank heater in the water (seen at lower left, below) to keep the tank at whatever temperature I want it. Note the thermometer in the lower right.
Shortly after this was photographed I cut the legs of the rack down a little bit to allow more headspace for growing. I also added an angled drip-guard made of lucite, to protect the cakes. On the left hand side there is another piece of aquarium hose, which is anchored just off the surface of the water. That is the CO2 exhaust. When the terrarium is occupied, I use medical tape to seal the lid hermetically - this keeps stuff out and also maintains a slight positive pressure in the terrarium. The only outflow is the CO2 exhaust hose, which, since CO2 is heavier and sinks, serves to maintain air exchange.
One of the nice features of this set-up is that you can have the air exchange (controlled by the aquarium air pump) on a separate timer from the humidity control (controlled by the ultrasonic unit's power supply). You may want to do something like run the air pressure only during the day and the humidity all night long and intermittently during the day.