So we got a can of Coopers German wheat beer kit, and decided to do 2x10 lites batches, trying slightly different recipes with each one. We boiled up orange zest and corriander seeds and added the liquid to one of the 10 lite batches, and for the other we just added the coopers brew enhancer kit 1 instead of the sugar, to see what it was like.
The step which may have messed it up: I rehydrated all the yeast in a (sanitized) jug and added half to one and half to the other.
Both OGs were similar in the 1052-1054 range, both about 22/23c.
The one we added the orange zest liquid went into total overdrive - bubbling maybe every 5 seconds for 2 days, and has now completely stopped.
The other one (with the brew enhancer in it and the slightly higher OG) hasn't bubbled once.
I'm hoping someone might have some pointers for where I went wrong - it was the same wort and year, the fermentation buckets and air locks are both the same. Some small differences in recipe. My guess is trying to halve the rehydrated yeast was probably a bad idea?
I'll measure both gravities tonight and update this question. I'm just wondering why two very similar fermentations have acted so differently!
I measured the gravities and they were both about 1.010, so it looks like fire.eagle's advice was correct!