martha box
https://www.youtube.com/watch?v=PqAyAUTiOB4
https://fungiacademy.com/mushroom-fruiting-chamber-martha/
http://www.mycoblog.com/martha-build/

 
General Parameters for a Martha Mushroom Fruiting ChamberHumidity


FRESH AIR EXCHANGE - ESTO ES UN TEMA: You will want to position your greenhouse near a window or in any place where you can easily exhaust to the outside (more on this later). Mushrooms release millions, billions, and sometimes trillions of spores, called a “spore load.” Oyster mushrooms have especially prolific spore loads. Inhaling this load is not good for your lungs. YOU NEED TO EXHAUST YOUR GREENHOUSE TO THE OUTSIDE.
Según esto deberíamos mover la caja para que tenga una salida a la ventana... 
o... (para el prototipo n.483) quizás se pueda reciclar el CO2 producido para otro cultivo? Qué pasa si conectarmos la salida de ventilación a otra caja/espacio de cultivo que sí come co2? 
cuestión de las esporas... quizás algún filtro, que atrape las esporas y luego las podemos liberar por ahí... 

Hello friend,  I have a question about the exhaust on the Martha. I have to have this in my basement and only have glass block windows. I’m wondering if there is another way to vent. I know if you have no where to vent a dryer. Hardware stores sell a canister you fill with water and then hook your dryer hose to it.  Do you think this could be an option?                                
                                                                
                                        
Using the humidifier we recommend, you will already get some fresh air exchange every time the humidifier runs as that model pulls air from the outside environment. But this is oftentimes not enough oxygen, especially inside homes (where carbon dioxide levels are higher than outside) and especially with Oyster mushrooms, which are sensitive to carbon dioxide.
To provide additional oxygen, your fresh air intake system can be as simple as slicing a few slits along the bottom, middle, and top of your greenhouse, then covering them with fine mesh screening to prevent bugs from entering. 
Or, you can get a bit more technical and invest in a few 4-inch (10 cm) air diffusing ventilation ports. Either way, the goal is to provide some passive fresh air exchange while keeping out bugs.
                                        
air diffusing ventilation ports: https://www.amazon.com/HG-POWER-ventilaci%C3%B3n-6-0-integrada/dp/B078RM2CX7/ref=bmx_7/138-9070626-2062311?pd_rd_w=sdtWr&pf_rd_p=3fe6199d-a167-4e56-abe0-5c5bb64370d9&pf_rd_r=A0Q07ZAP6FQEB2VN1YK3&pd_rd_r=a53b373f-7915-464b-bb0f-5950f48e746f&pd_rd_wg=aTsY2&pd_rd_i=B078RM2CX7&psc=1                                               
                                
humidificador
https://www.youtube.com/watch?v=NtfuuThTTgg

para el tema temperatura, comentario al artículo de fungyacademy:
    Love this set up! Wondering, is a multi layered entry for humidity necessary? I actually put a air purifier at the bottom of the tent with a heat lamp on bottom of a metal tray with lava rocks submerged in water. The heat lamp heats the lava rock causing water to evaporate and the air purifier then sucks it in and distributes the heat evenly. Also blowing the humidifier Fog around so not sure if the multi level would be needed in that retrospect. Just love to hear your thoughts about the tek

desde Shoomery:
    
https://www.shroomery.org/forums/showflat.php/Number/11050932

Put the humidifier inside and on the bottom of the Martha.  Place it on the floor of the Martha and to the side of the shelves so they aren’t being blasted by the vapour.

Depending on how clean your tap water is you should be fine using it.  If you have really hard water you can use distilled water to help reduce/ prevent mineral build up.  I have read, however, that RR does not recommend using distilled water in your jars, etc; rather, to use either tap or spring water (if this is incorrect, somebody please post a response but back it with with evidence).

You MUST clean the unit at least once a week, and change the filter when required; otherwise, mould and other gunk will build up and wreak havoc.

The time to worry about contamination is during the inoculation and spawn run stages, not the fruiting stage (tho it is still a consideration). To protect your crop from contamination during the fruiting stage, the answer is the more FAE the better.  Not enough and mould, etc can build up.  

The humidifier is not for FAE, only for humidity.  Cut a few slits in the walls to allow for cross venting and FAE (or make a couple of windows).  The air turbulence inside the Martha caused by the cool mist will draw fresh air in thru the slits and also expel air.  The Martha should also ideally have a gabled roof.  

A cool mist by itself 24/7 is serious overkill for a greenhouse as small as a martha. He suggests to have it on a timer set for 2-5 mins on and 6-10 mins off.  This will, of course, depend on the ambient temp and humidity, size of greenhouse, etc. so you’ll just have to play around with it to suit your needs. He uses this timer (scroll down to the repeat cycle timer) http://www.littlegreenhouse.com/accessory/controls2.shtml or something similar that allows you shorter intervals. 

You get moisture build up when the cool mist throws out water faster than the air can absorb it.  Shorter cycling with a timer prevents that problem. As you're tweaking the system, lay wax paper over your substrates to protect them from too much water.  Essentially, you don’t want water build up on your cakes or fruit.  If water droplets are forming on your walls, etc then you need more FAE... possibly cut more slits and/or shorten your misting intervals.  Bottom line, you want 95% humidity and lots of air exchange, with no standing water or moisture on the walls or floor.

Take some plastic sheeting and make a “diaper” on the bottom of the Martha and put trays of perlite on the floor inside. The trays of perlite absorb drips that fall when the mist penetrates shelves and some of the water droplets adhere to and then drip back down. If you don't use perlite, you'll likely have a mess on your hands. The benefit of perlite trays on the floor is that they return the drips that fall into humidity in the air.  You should also fill any empty shelf space with trays of damp perlite.  This will help you maintain good humidity, and you can then cut more windows or slits for FAE.

bucket humidifier:
    https://www.shroomery.org/forums/showflat.php/Number/16598472#16598472