I'd say yes! Peanut butter is probably one of the most-acid inducing foods because it is primarily fat. It requires more energy to digest (just like any other fatty food), which requires more acid to do the job. Lay off the PB, and switch to a low-fat carb-based diet. Simple sugars are easily digested.
Japanese millet is most successful when planted on prepared soil, although Japanese millet will germinate and grow just about anywhere. For Duck food plots, plant the Japanese millet early in the summer (June-July) depending on the start date of your duck season. Japanese millet seed heads will hold on longer than most millet varieties, even in standing water. The seed will slowly drop out of the seed head feeding the ducks over time.
Mallards hatch early, within 26 to 27 days. Pekins and most common breeds of duck hatch at 28 days. Moscovy ducks are on the longer end, hatching after 35 days. Eggs are not laid all at the same time, so they will not hatch at the same time. Sometimes a mother begins to incubate some eggs while others in the same clutch have not been laid, so some variance in these days can be expected. Once hatching has begun, a duckling can take several hours to emerge.