DD is 8 months and still one the first size teats. We use Gerber bottles. For the last few weeks, she's been pushing away the bottle after a few ounces and I thought I'd try the next size up, which is called Fast flow (haven't found any medium flows). Well the milk just flows out of the fast flow teat and she invariably chokes and dribbles, so I went back to the regular teats. She takes about 17-20 oz of formula a day, so maybe a bit on the low end. Suggestions any one?