Feed them every other day and only as much as they eat in 5 minutes after they start eating. Jessa posted some great pics on here of her frog just after he ate. I just noticed them the day before yesterday. The skinnier one does not have them. That sounds opposite since the males are usually the skinnier ones.
Females sometimes have a little nub on their vent.
Pellets and fozen brine shrimp right now. I am looking into getting brine shrimp eggs and hatching for live food. The freeze dried and pellet type food are not good for the frogs and can cause impaction. Frozen shrimp are fine, so are frozen blood worms. Live is nice, but frozen is much easier to deal with and keeps easier than live feeders.