Dunkleweizen and tartness

I have a question for anyone that may know. I made a 20 gallon batch of hefeweizen with my friend and all of his turned out great, but mine was tart like lemon. I assumed it was infected, but my friend is a sanitation ****. Anyway, that was WLP300 and I'm not sure what temp he did the fermentation.

Now, I made a ten gallon batch of dunkleweizen with another friend. He used WLP351 and I used WLP300. Mine is great! His has a slight tartness..not infected tasting, just a mild tartness. I fermented at 68 and with everything I did there is no way it could be infected.

One friend said that wheat sometimes causes a tartness and I should back off the amount in my recipe. Another said it just sometimes happens with this kind of yeast if it is fermented at higher temps. I'm not sure the first one was infected and I'm 99% sure the dunkle wasn't.

I'm really not worried about the hefeweizen. Has anyone experienced a slight tartness with WLP351? Is this common with these yeast types or wheat beers?

 

It is definitely citric. Like lemon. So, you think it was the yeast? The only thing we did different was that his was in a glass carboy. We siphoned it into a bucket like mine and followed sanitation methods to a t. But we did siphon off the cake at 5 days. at that point we were not at our target final gravity and the sample of his tasted good. Is it possible we took it off the cake too soon and strained the remaining yeast to work too hard? Was the ideal temp for WLP300 not the same as the WLP351? Cuz mine tastes great!

 

Here is the recipe if it will help: 10 gallon batch:

10 lbs wheat malt
8 lbs munich malt
12 oz special B
8 oz caramel wheat
8 oz caravienne amalt
4 oz carafa II
4 oz chocolate malt
2 oz hallertau (60)

One had WLP300 and the other five gallons had WLP351. Mash was 154 and sparge was at 168.