It’s RDWC. The emitters are clear, so no problem there. Besides the root mass sits in water
Before I started first week of flowering from veg, I drain the entire res, fill partially and drain sediment at the bottom, repeat until water is clear, then refill w new nutes.
I’ve had it on 6 feeding at 10 mins, thinking it may be too much I’ve reduced it to 4 now
Yes, that’s what I suspect is starting. That’s why I’ve added UC roots now so it doesn’t spread. Other than that, I’m baffled.