Soil for seedlings?

Hey all, looking to start my second grow in solo cups with gentler soil, then transplant into full 3 or 5 gallon fabric pots with FFOF, tried starting seeds in straight ffof and some of them were being burned from the amount of nutes. Any suggestions on a soil for starting seedlings for my application?

You can just add in some coco and perlite to FFOF to lighten it up. “Spent” FFOF works well as is for seedlings too if you have any left over from a previous grow. Adding in some ewc will help develop young roots.

Jiffy peat pellets or starter mix.