I have herd of it being a little too strong for seedlings as well. I am surprised that the FF was Compared to the Promix since one is a soilless bass. But ya, people love that Ocean Forest and it can be used with the FF additive packs with good results I have herd, but remember the FF additives can be strong for some nutes, but still many work up to full strength with no problem. I would use it, but I can't find it in my city.
Adieu