These are growing really well - just boring, steady progress. I've dropped down to 800 PPM and all signs of early burn have stopped. I think staying on the low-mid end of the GH feed schedule is going to be just right moving forward. Deep, obvious purple is visible on some fan leaves, on the edges on others, and not at all on still others. The smell is mild but noticeable. So far so good!
@BigDaddyK, It's all good - I'm hanging it up with this RDWC, though. I'm growing in a garage in the desert and to keep the water temp low I'll have blast the A/C. I'm buying more autopots and packing this system up until December!