Hi. my twins left hospital on aptimal prematil ha. they are both now between 3500 and 4000g. they generally drink around 120ml each. i asked the hv about which milk formula to go on next,but she said if they are happy on the one above to stick with it. if this is the case why have so many different types? not speaking fluent german, we do not have a clue which one if any to go on next? sorry to prattle on, but would like some answers. thanks