Check your pH. Citrus zest is pretty acidic. If the beer's pH is in the low 3 range, that could cause your yeast to shut down. If that is the case, raising the pH back up to around 4 would allow the yeast to reactivate and finish fermenting the beer.
A lemon/lime corriander weissbier sounds pretty tasty!
I'm sceptical that citrus zest is acidic enough to significanly lower the pH of 5 gallons of beer - unless rightasrain used the zest of four bushels. I'd look more at yeast health, wort oxygenation and fermentability, etc. I doubt the zest has anything to do with it.
Perhaps the oxygenation then. The reason why I wouldn't think its the yeast health is because i've re pitched yeast. I did stir it vigorously in a better bottle to hopefully get more oxygen in there and added some yeast nutrient. But that was after re-pitching maybe the yeast already went into the secondary stages before the stirring. I forget the term but the hybernation mode is how I think of it. There is a yeast cake on the bottom. I may have not been able to stir well enough to get proper oxygen in though. The small opening of the better bottle makes it difficult.
Thanks for the tip on transferring to the second only after fermentation is complete. I will remember that in the future. Although I might quit using a second as it seem's most people disagree it does any good.
I figure the next thing to try is to transfer it back to another fermenter I can stir better to get more oxygen in there. Any other ideas on what I might try next?
To all the questions, forgive me if I missed one.
I used the zest of one lemon and one lime fresh from the store. Microwaved for 30 sec to sanatize.
Its a boxed extract recipe. http://www.midwestsupplies.com/lemon-coriander-weiss.html
to be exact.
And so far its really tasty.