how can I tell my beer is fermenting?

So I just brewed my first batch (a pilsner) yesterday, and have not yet seen bubbles come emerge from my airlock (its been about 30 since I started fermentation).
Possibly useful information:

I used 1 package of Muntons dry yeast that came with the ingredients kit. Before adding it to the beer I re-hydrated it into 1 cup of boiled (but not boiling) water, and proofed it with 1 tsp. sugar in about 1 cup of water...30 minutes following the insertion of the sugar solution in the yeast solution, the majority of my yeast had settled to the bottom (I didn't see a reaction, as I was told should happen)....perhaps my yeast was bad, but I just chalked it up to having too dilute of a sugar solution. When I stirred the solution, I did see fizzing, so my gut instinct was that the yeast was taking the solution.

I'm not sure how good of a seal my fermenting barrel has: The airlock is inserted in a hole on the lid of the barrel, but it is definitely not airtight...the co2 could be escaping via a leak, not the airlock, which could be the reason why I dont see any bubbles.

Would anyone have any suggestions as to another way I could check my beer is fermenting? If its not, I was just going to throw in another packet or two of yeast, and see if that does the trick.

thanks much, all who were patient enough to read this overly-analyzed log of a first attempt to brew...

you should have really seen a reaction when you rehydrated it. i would get some more yeast and repitch.

oscar78 said:

...I re-hydrated it into 1 cup of boiled (but not boiling) water...

Click to expand...

I hope by "not boiling" you mean cooled to below 100 degrees?

30 hours is not a drop dead time line. I'd give it another day or so. Did you take hydrometer readings. Don't depend on the airlock to tell you what you need to know about your beer.

Get in there and get a hydro reading and that will tell you the progress of your brew.

If you pitched at not-quite-boiling temp? Go buy more yeast. It's cooked.

Here's a few tips:

1) Take some plastic wrap and wrap it around the top of the carboy, over the rubber insert and halfway up the airlock. Then twist your hand around the plastic wrap till it is tight. That will seal any CO2 leaks.

2) You should always pitch yeast at around ~80 degrees. It's wakes up the yeasties. If you shock your yeast in any way, it really throws them off their game. My 2nd batch, i did a 3 gallon boil and after cooling the wort to 80 degrees i pitched my yeast. Then i accidentally added 2.25 gallons of top off water at around 60 degrees. My fermentation took 48-72 hours to start. Normally i see some kind of activity within 10.