How much oatmeal in formula?

Heather

Before anyone tells me how bad is to put oatmeal in my baby’s formula his pediatrician told us to do so because of his severe reflux.

What is the amount of oatmeal I need to put in a 90ml bottle? No matter what I do I can’t find the right ratio. It’s either so thick it can’t fit through his level two nipple or so thin he gets strangled. I even milled it up in his baby bullet where it’s almost a powder and I still can’t get the right ratio. Any mommy’s have the right ratio to get it thick but not too thick to get stuck in a level two nipple