Growth continues to be vigorous with more tops reaching 5'. I noticed slight burning on the tips of some of the leaves, so I backed down to 900 PPM and it abated. The smell is still mild.
@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!