I don't know what 'fertiloam' is, sorry ... one thing off the top of my head: if the seedlings just 'fall over', with a section of thinning stem, they have Pythium Wilt, caused by too-wet soil ... cool soil temps accelerates it ... now, I'm wondering IF the rockwool, rapidrooters, (whatever you're using), are transplanted into the soil too wet, and holding that moisture, long enough to develop PW ... ??? ... just an off-the-wall situation to look for :jointsmile: