I'll reply to everyone at once:
Can't stake, as this is hydro. Used trellis as an emergency prop, didn't get installed in time to use for proper scrog.
I've been using silica (pro-tekt) from the get-go. Doesn't seem to help.
I used a small fan from the beginning, but found it to be perhaps to strong, the seedlings died/dried out too early.
Everywhere I've read said to not have fans blowing directly on plants or you can get wind burn (which I've had in the past). Probably too late to adjust fans in an attempt to get strong stems now, is it?
My PPM is about 900 now. Using 3 part nutrients by G.H. Ph is around 5.9, swings a bit lower, bit higher. Temps 74 - 84 f. Lights out during the day. Grown in basement.
It's a weed, so it does generally grow no matter what I do, unless I totally screw it up or get an infestation or something like that. However, hoping to figure the next grow out to get stronger stems/branches.
I noticed
Diabolical666 has strong branches, but those are outside in soil, so probably makes a big difference.