Just start adding them in, crushed, doing additional pwc
's. Just to keep them safe and growing strong.
I would start though with baby fish food, there are additional things for growing baby fish they add in for wellness and growth. Keep feeding them some baby brine. There is frozen available too in case you are feeding home grown bbs.
Often found in saltwater fish stores (ask for them, or for them to to order them in for you if they keep frozen foods), sometimes in the freshwater stores.