In a pond setting I would start with number one. That also works in a tank setting. Number 2 I would not even waste time with in a pond setting as natural forages should still be helping them along. The 1" fry will peck at the 1.5 mm just fine. Logic based in part on you will not be able to use all the smaller feed size before they grow beyond it.
Belt-feeder better than hand feeding to be sure. If possible make so feed falls down into partially shaded area with feed ring around it. The crumble will sink but the 1.5 will tend to float away from where the fish feed.
