High Final Gravity

[TNT650R]

For a high gravity beer like that you'd be better off using pure oxygen to oxygenate your wort as the maximum amount you'll get from air is about 8ppm of O2 and the yeast will need over 12ppm of dissolved O2 for optimum growth and fermentation.
So even if your wort spray aerator can give you 8ppm you will still have problems with underattenuation. Also as stated above oxygenating again at 12 hrs is advisable.

yep!the acquarium pump isn't the best way....
I red an article on BYO some years ago, with a contest of different areation....If I find the link I will post.
but the pure oxigen is expensive and for small amount I think that the best thing is to stir vigorously for some minutes!
I always done in this way also with gravity higher than yours without attenuation.problems.
oxyigenate after 12 hours...I don't like this thing....if you give enough amount of O2 in the beginning, don't need this thing...because if the cell has enough O2 they start the reproduction and than they will continue..without other O2..

 

[manticle]

High mash temp + lactose and roast grain and caramel malt is always going to finish high but why not do a fast ferment test to see exactly how high?

 

[HalfWit]

Thanks guys. All quiet interesting. The double dropping idea seems very easy. Sometimes I have to wait for a while before pithing at Lager temps.
Thanks tdh. When put like that, working out the attenuation is easy. I have never heard of fast ferment but I will give that a go on the next batch. It's down to 4c so I will keg today.
Sorry for going OT but I am looking to brew a Lager using Amarillo and Cascade. I can't find much info on grain bills and yeast anywhere. It has to be done at Lager temps and using Pilsner grains.