Maris Otter 94.23%
Crystal 400 4.49%
Chocolate 0.64%
Tor.Wheat 0.64%
Normally I'd use Nottingham yeast, but sourced some S-04 [mixed with some S-05] from a microbrewery, so have used that. Fermentation temperatures have been between 20.5 - 22°C since Friday night.
Yesterday, the SG was 1.013. With Nottingham, I'd have expected to reach a FG of 1.010 - 1.011 by then. I've left it for another 24hrs, but it's hardly budged.

However, there is still quite a lot of yeast floating on the surface, although there isn't much sign of activity.
Is this normal? I was under the impression that S-04 acted in a similar way to Nottingham, and dropped to the bottom to make a thick sludgy pancake.
Do I just need to be patient for it to ferment out the last few points? At the moment, I have a beer of 3.4% instead of the 3.7% target.
Right now, the temperature is showing 20.4°C. Maybe it needs warming up a little?