FFOF is a great soil if you use it correctly. I use routine transplants. From solo cups, to 1 gal, and finish in three gal. FFOF has enough nutrients in it to carry a plant 6-8weeks without any additives except water. I dont use nutes in veg anymore. I only use them after the 3rd week or so in flower. Since you said your temps and humidity are great, the main thing to focus on is the ph of the water you use. You said you were gonna start using distilled water. Yes the ph is really low in distilled. It will be even lower when you add nutes so make sure you get it back up to the 6.5ish area. Here's a little chart that might help you along the way.
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