peat moss

I have a sprout in a plastic cup with 75% peat moss 25% sand. I have found out that peat moss is highly acidic and would be harmful How should I act? Should I repot in regular soil? And at which stage/seedling size would a transplat be neither late nor unsafe?

Im doing a passive hydro with a peatmoss soilless mix(sunshine mix#4) and i heard that if you mix clay pellets or rather put a Layer of clay in the middle that u can increase drainage in turn resulting in more frequent waterings/fertilzers with less chance of salt build up and nut lock...