Seedlings need plenty of calcium too; you'll have to read the schedules for the answer to your dosage question, but I've always just used tap water on mine. If you have to use DI/RO/rain, my hunch is that you still need calmag, but at a lower dose.
stinkyattic Reviewed by stinkyattic on . If you use RO or distilled water you NEED CalMag Plus That's all. My fingers were cramping from typing it n times a day. Rating: 5