Slow Start

[Coppo]

Coppo,
Whilst the krausen ring of confidence will confirm that your yeast has entered the anaerobic / attenuative phase, you might not have much sediment in the bottom of the fermenter due to the nature of the brew - your recipe will not have much trub or cold break matter and the relatively modest hop bill may be hard to spot in the fermenter (assuming you aren't using a glass carboy).
It's possible that your yeast is still going through an extended adaptive phase, with the possibly small and strained population of viable cells working hard to add to the overall population with the existing nutrients (sugars) and the oxygen in the wort - you may not know it but the malt extract won't have much in the way of amino acids and other key nutrients to assist in cell wall nutrition. In fact, the best nutrient base for building yeast starters is to do a mini mash from grains.
Before you retire for the evening, I'd suggest you sterilise your stirrer, take the lid off and give the wort a good whirlpool to rouse the yeast through the solution. If the wort shows no action in the morning, call it a dud yeast, and add some more - if the HBS is nearby, grab a couple of sachets of W34/70 or whatever dry lager yeast they have, out of their fridge stock and sprinkle directly onto the wort surface for a quick and easy fix. You should have action and a fermenting lager within 12 hours.
Cheers,
TL

TL, and all,
ended up getting another S23 yeast from the HBS. Put it in, still took 2 days to start bubbling. But all is good now, very healthy airlock activity.
Just hope it tastes alright.
Cheers for the suggestions.

 

[Piste]

I have a lager on the go at the moment and it took a couple of days before any airlock activity, when it did start it was slow and stopped after two days, I gave the fermenter a bit of a violent shaking and within 12 hours it was off again and has been going for just over a week now.
I am at the stage I wonder when it is going to stop!
Fermenting at about 15 degrees, a lager kit with 1kg of Newcastle brown additives for our local HBS (a mixture of dex, dlme, hops and grain, quantities are a secret) and Saflager.
Pity I didn't do an OG so I have no idea where this one is going.