Just let it run and see if you are seeing areas where detritus is building up aka dead spots. Honestly corals are pretty adaptable and as long as you aren’t blasting low flow corals with tons of flow they’ll do fine. Softies and
lps even though they’re usually listed as lower flow corals still appreciate moderate flow over them. You usually get a grasp for where to put stuff as you go. Do you have a tank pic with the orientation of your power heads? That could help to narrow down areas as well.