I have built a grow box similar to that advertised by many: A plastic box with holes 2 inches apart drilled at all six sides and 1/4 inch drill bit used (advertised by Willy Myco on YT) and shown here:



I don't understand this concept.

First, the perlite easily falls through the bottom as the holes are pretty wide (6 mm or so) so I had to cover them with micropore tape.

Second, the box does not hold any humidity - even with lots of wet perlire, the box has basically the ambient relative humididty (about 49%) but should be >90% ... and the cake casing is dries quickly.

The PF tek does not mention such issues so I am confused. Some people say I should use a closed box and ventilate it often but some say the FAE (free air exchange) is vital.

Can you please advise?

In my monotubs wet substrate (coco/cow manure compost/vermiculite/straw) maintains high humidity for a long time. No need for FAE if using holes (mine are on the sides in two rows and filled with polyfill, aka pillow stuffing). Did you close the lid? How good of a seal did the lid have?

Recommend you move to pasteurized substrate soon if not planning to do so already. Much higher yields. Simply put the closed tub with wet substrate mix in the oven at low tremp till it gets to 150C (probe with baking thermometer), cool, and crumple up cakes into it at 50% volume.l while working next to a small personal HEPA air filtering unit. Cover and forget about it until harvest time.

I'm still trying to get through my flushes and it has been over a year.

Attached are a couple pictures of my monotub in case it helps. Fits perfectly in my oven. Cheers.

Thanks. I realized the humidity measuring was built in the digital thermometer and not the attached probe, so it measured outside humidity. So I placed the thermometer inside the box and it shows 83% RH.

I stick with PF tek since I don't have a pressure cooker (the large ones cost a small fortune), have plenty of BRF and also not needing high yields - it's just for starters. Then maybe I will order All American PC as the ones sold in Europe are either too small, don't have a gauge or don't provide enough pressure.

Right you mentioned that in the spores and agar thread. Once you have the cakes colonized you can go to substrate monotub since they only need pasteurization at 150C and not sterilization for the crumpled cakes to colonized the monotub.

Now that you have a growing chamber you are only two steps away: add organics to the perelite and pateurize. The crubled cakes will colonize the water reservoir and you will get a breath taking flush if all goes well. I'd do it just for the fun of it (and ended up with too much).

Okay maybe I have some spare boxes so I can try a small monotub.

All monotub tutorials I found were strict about pressure cooking and used grains. I don't have access to manure, gypsum or other items plus I am extremely busy and having space just for that one big plastic box in the appartment.
I am pretty sure if I play with substrates and try to mix something without heving absolutely precise recipe, I will f**k up.

I haven't had my first flush yet so I will stick with what works so I get at least some fruits and then maybe play with monotubs.

How much organics and what kind?

I know about horse manure, but there are many kinds: two-part, three-part, pelletized, with "padding" etc.

Even gypsum is a problem, there is grey gypsum, white gypsum, gypsum for building, for electricians...

I know it's easy for people who grow stuff and know the products but it's hours of research to get every step done for me.

Sounds good, sorry if I'm pushing the monotub, it's just that it gave me so many good memories I want to spread and share.

I've tested without gypsum and have had not had issues. I dropped it because I read that excess salts from mushroom compost can hurt seedlings/plants.

I'm more than happy to help when/if you are ready for monotub. Let me know.

It sounds like youre trying to set up a shotgun fruiting chamber for your cakes which can still work pretty well without any bottom holes as long as you have them all around the sides. You could also benefit from placing a small fan in the room. With this kind of setup, its necessary to mist several times a day in order to maintain the proper humidity. Monotubs are still the best way to go unless you have a greenhouse setup but if youre not trying to buy a PC (highly recommended) youre basically limited to pf cakes

I checked with digital humidity meter and it consistently shows about 95% RH (99% when light is on) and there are droplets of water inside all the time (even if not misting).

Now I uncovered more holes and misting once/twice a day to compensate for water loss by evap. and the shrooms are doing just fine.

It seems the humidity skyrockets when lighting is on, the flurescent tube produces suprisingly high amount of heat.

I don't want to uncover bottom holes as the perlite falls through making mess and don't want to uncover top holes as the water vapor may damage the light tube, making electric shock hazard.

Yes I will buy a PC, but don't want to buy some small one (most don't even have a spacer) so I am saving on an 18L autoclave.

BTW Nice to meet you Rick, I hope Morty's doing well (at least in this universe )

Sounds like you have it pretty much dialed in! A PC is a bit of an investment but once you have one its an incredibly valuable tool. I think I might have spent $80 on my 22qt PC but I can fit 9 quart jars in there pretty comfortably and I use it at least once a week so its definitely a vital asset. Nice job on the fluorescent tube, I'm going to need to get one of those myself soon. Morty has like 5 monotubs going right now and he needs to light them all properly. He gets his culture isolates from his grandpa of course

Yeah I will finish my BRF bucket and then move on to grain.

I heard somewhere that even with PF Tek one gets more mushrooms than he can ever consume so I sticked to that but it seems it does not scale up that well.

Unfortunately I also read that growing through winter is a bad idea so it seems the big monotub grow has to be postponed to spring.

As long as your grow area can maintain at least 60 degrees F you can still grow as much as you want, it’s just a little slower than usual. Morty grows right through the winter and the thermostat usually sits between 60-65.

That's good to hear. The temperature never drops below 66 F (19 C).