Not looking good!

[Portreath]

Pale ale three week in and stuck at 1.024, added yeast nutrient and more yeast and a week later still at 1.24 with nasty looking white growth.. FUBAR me thinks!

 

[foxbat]

That certainly looks like a pellicle to me.

 

[Portreath]

Drain fodder?

 

[stz]

Drain fodder?

Your choice. I've only had one random infection and it wasn't a good one. Kind of musty, dusty with hints of sick. The chance of getting a good infection by accident is slim. You shouldn't need three weeks for primary fermentation, that length of time is indicative of wrong pitch rate or wrong fermentation temperature. You shouldn't have a normal pale ale finish at 1.024, indicative of something iffy with the recipe or process (mash typically). Repitching isn't always the best cure for a stuck fermentation, yeast nutrient is generally not needed except under specific circumstances such as atypical grists and the demands of specific yeast strains.

 

[Portreath]

The brew is (was) a simple single hop pale ale. 4500g MO and 350g Crystal. Boils was 60 mins.
Mash temp was 65c for 60 mins. which gave me 24 ltrs with an OG of 1.044. I pitched 1 packet of CML ale yeast at around 20c, fermentation kicked off but after about 3 days stalled. I'm going to bin it, but would like to know what went wrong so I can learn from the ballszup.

 

[The Baron]

option one ditch it
option 2 syphon from under the surface into a new FV and repitch - no guarantees of anything though

 

[cheshirehomebrew]

Possibly the CML yeast needed more oxygen in the wort hence it stalling them spoiling ?

 

[Portreath]

Thanks. I will keep that in mind when I pitch for my next brew.

 

[foxbat]

Thanks. I will keep that in mind when I pitch for my next brew.

What did you do with this one?

 

[stz]

How are you testing gravity? Hopefully hydrometer! If it was refractometer and you didn't adjust it might have been a lot lower/done. Based on your recipe and mash schedule assuming everything went to plan it really sounds like you took a final with a refractometer and didn't adjust for it. Are you calibrating your mash thermometer? If your mash was actually a lot hotter ... well I'd have still expected it to finish lower to be honest. I personally wouldn't worry about oxygen, dry yeast is pretty good for a single ferment without any oxygen.