Love it. It burps. Low profile and no hassle like airlock or blowoff tube. And if you drop temp it will not suck in water or air through airlock or blowoff tube.

Yes. I've used it for many batches.

That will depend on the amount of pressure your container is under really. I use these for secondary wine racks and the pressure is much less than the initial fermentation. Even so I have still had a few blown out of the container. If your pressure is lower I highly reccomend these.

Yes I use it for beers and works well

It should. It's just the bung for a 5 or 6 gallon pet carboy. I love them. I don't have to refill them and they have a lower profile so they can't get knocked out of place.

Yes from a fermentation venting standpoint they are the same. CO2 Sulfur Dioxide you name it.

Yes it will. I would suggest a blow-off tube first until the yeast gets settled down unless you have crazy head space. Then go with this. Otherwise it is a PITA to clean and can get moldy if you don't get it cleaned perfectly.

Yes it works well for beer once there is no danger of blowoff. Cleaning krausen out of this thing would be a pain. These are especially useful for aging sour beers - no need to keep an airlock topped up.

Definitely works well for secondary fermentation or moving the carboy around. I still use a blowoff setup during primary fermentation which helps avoid clogging blowing off the top or mess.

Works great for beer too.

I use it for my ciders and love it

I can partially answer. Caveat emptor: I don't have a FerMonster carboy. The whole idea of these bungs is that you can't suck in air through the airlock yet the gas can escape under positive pressure. With bubbler type airlocks you can suck in air if your temps drop which is "not good." When I look at the pictures of the FerMonster carboy I'm most concerned about the air-tightness of the spigot when "closed." I haven't had great luck with this sort of spigot. If your temperature is stable I don't know why you'd develop a vacuum. However if your temperatures swing down at night you might get a vacuum... I'd be concerned about air bubbling in through the spigot. Some ideas to mitigate: 1) use a thermostatically controlled heater belt around your carboy if you can find one that doesn't need a thermowell bung or alternately use an insulation blanket or space-heater. 2) Some food-grade silicone grease in the spigot might make the spigot more air-tight or maybe the spigots are more air-tight than the similar ones I've used. These bungs are cheap and are a great tool if they will work for you so why not give it a try and let us know how it goes...

This is exactly what I use them for. I have a small temperature controlled refrigerator I ferment in and this bung allows my FerMonster to fit. I have had no issues. Has the wort is cooling still in the chamber I will vent the cap maybe once before I pitch. I have had no issues ever with contamination using these. I do however take them apart and sanitize after each batch.

So long as you didn’t push to close to the max volume you’d probably be fine using it in a fermonster. I’ve used these for aging sours in thick pet carboys and still got quite noticeable deformation but I’ve also accidentally left closed transfer lids on my fermonsters when draining sanitizer a few times causing about as much of a vacuum as you could imagine and they’re still working fine after being inflated under light pressure despite being pretty crumpled up by the vacuum. These breathable caps are definitely not for primary fermentation though a vigorous fermentation would push them out.

Since the FerMonster is plastic there is not really a big issue with vacuum. The fermenter will slowly draw in at the sides until there is enough vacuum to break the seal on the bung.

Use a sanitizer solution. Lift the lip under the water to flush sanitizer through them.

The silicone is naturally hydrophobic so for my uses it really rinses clean with water. The top is essentially a flap that you can manually lift on one side while you rinse through the holes. I then submerge it completely in sanitizer and again lift the edge of the flap to allow the liquid to cover asado surfaces inside and out.

Very hot water upside down and flowing thru then followed by either a brand name chemical cleaning (or metabisulfate) and/or thin flexible brush with top cap gently pulled back. Jack

I drop them in warm PBW overnight. Clean's them right up. :-)

A little brewers wash and water does wonders.

The top sealing flap pulls out. A little soak in cleaning solution and small tube brush will work.

Its flexible and there are holes under the lid... you can soak them in sanitizer and use soft bristled brush.

They come apart I soak in cleaner and if really gunked use a pipe cleaner to get in the small holes. They work great.

Soap and hot water

I wash/soak mine with a mixture of OxiClean and water.

Just rinse in water.

The #10 Silicone Bung does not fit on the 20/30L Speidel fermenter.

I don't know if it will fit but does replace an airlock. I have bought numerous sizes of these bungs for carboys demijohns and different barrels.