blow-off tube problem

Hey fella's
I've never had this happen before. I brewed a stout last Saturday. Had the blow off tube in place with about 4" of water in a qt jar. The car boy is in view all the time. This morning I noticed the water was gone from the jar! I don't think it evaporated that fast cuz I looked at it yesterday when I got home from work. Do you think it got sucked back into the carboy? The blowoff tube is about 16". I normally only keep the b/o tube on for a few days that put a regular airlock on it....hope the beer is ok...
neil

Do you have a cat or dog? I can't think of a reason fermenting beer would "pull" water back that far... or that completely... beer should be ok, the co2 is going out, not in.

Hi... I should have mentioned there were no pets in the house....it may have evaporated and I just didn't pay that much attention to the level of the water when I checked it yesterday....we have the heat on most of the day and off during the night....
I guess the only thing to do is bottle it and hope for the best...
tnx for the reply...
neil

I brewed a stout the other day and placed it on a yeast cake from a brown. The fermentation was violent. After the first day the airlock was dry. I guessed it was from the amount of bubbles coming out. I just added some water and it ended up fine.

it could have evaporated. i have a ten gallon fish tank on the bar, and i'm topping it off with about three gallons every two or three days. it's dry dry dry now that the ground finally froze.

I think it may have sucked it into the carboy. I use a 36" long blow off tube so 16" seems real short

I agree with the sucking back in theory... What was the temp of the wort in the carboy? How much did it cool? In the end, you may just end up with a bit more beer!


-p

hi, how much headspace do you have in your fermerntor. You indicate that you turn off heat over night. The temp fluctuation would have a negligable effect on the volume of the wort. The head space above the wort however, would change in volume considerably with temperature change. so if the fermentation was rapid (not releasing much CO2 now) then as the headspace cooled it could have created a vacuum and thus sucked in the fluid in your blow off container. Of course evaporation will be responsible for at least some of the water loss. especially in the dry winter monthes. If it was plain water then, I'd bottle and hope for the best.
right on
brewfie

tnx for all the replies and thoughts....I was kinda leaning towards the idea that it was sucked back in as well. I think I may have just confirmed that too. I just checked the level in the carboy and it is higher then when I pitched the yeast! I was only water, but pretty skanky looking water. I wonder if there was enough alcohol to combat all the skankyness? moral of the story....remove blow-off tube after the vigorous fermention stops...
you guys have a good one...
neil

Yah, the headspace heating and cooling will definately mess with a blow off. By the way, why was your blow off tube submerged in skanky water? Wouldnt you want this to be pretty clean, regardless of the suckback?

Brewpilot

The water in the jar was clean on Saturday when I put the blow-off tube on, and since I normally put the regular airlock on after a few days, I don't change the water in the jar. So the jar water had a few chunks and floaters in it...
I keep the carboy in a plastic storage tub that you get from WalMart. I lined it with foil covered bubble wrap used for ac/heating (covers duct work etc). Sometimes if its real cold, I put a low wattage light bulb in with it to keep the temp up. My jar for the blowoff sits on top of this. That's the reason the tube is only around 16". I've used this arrangement for a few years and this is the first time I've had the problem. Maybe I've stumbled on to something!!! The first beer barometer!!

I brew 3 gal. batches. I used to do 5 and would do it now, but I'm limited on space and I don't want to load up on lots of brewing stuff like I had before. The biggest issue is the cooking on the stove top. But I've worked it out so it doesn't take that long.

I really enjoy reading the forums here on HomebrewTalk. There are lots of creative people brewing!

hop-on

Ah-ha!

If the water was above the carboy, then you may have had a siphon! I was bothered by the thought of the pressure change sucking the entire amount....

cheers, -p

Ditto....I think the siphon is the best explanation, the pressure change from the temp change is probably what started it.
I always use a blowoff tube and make up an iodine solution for the tube to sit in.

tnx for the info...will have to replace the tube for a longer one and place the whole thing on the floor next to the carboy. I'm just keepin' my fingers crossed that the whole batch isn't shot....
hop-on---

neil

The answer to this question without a doubt is temp and pressure change. The same thing happened to me. I had 4 batches of beer fermenting with blow off tubes but the bucket of water was below the carboys. Change in temp caused some of the water to be sucked back into the carboy. How do I know? Because when i racked to a secondary yesterday I would take off the blow off tube and watch water come back out of the hose. Hence why I looked for this post. I am just hoping that not to much water got sucked back in. My water too was pretty nasty. I changed the water after I didn't see any foam coming out but I guess some more did and made the water nasty as hell.