The directions for Holle baby formula say to boil water, let it cool, put 2/3 of the water into the bottle, then add the formula, then add the remaining 1/3 of the water (this is what my wife says, at least. I haven't read the directions for myself).
Is it necessary to add 2/3 of the water, then the formula, then the remaining 1/3 of the water? Or can we just add the full water amount and then the formula?