@Dee.S73, @Larry3215, I truly do value all input from experienced growers, especially in a medium that I have less than 6 weeks experience in, so thank you for bringing both points of view to this discussion.
I did a res change today and went halfway - 5.6. If the plants seem better, I will lower, if not, I will resume my course of 5.8. I will update the grow log once kid is in bed and link here.
The chart from UC says higher kn veg and lower in bloom, they may have a reason, but that is for their own nutrient line.
The root rot has not been back, and the roots growing out are pearly white with excellent branching.
I shave also lowered feed down to EC0.66, 0.06 of which is mag sulf, since I had to cut calmag down to 1/4 dose to keep the feed proportion at this low of an EC.
Also started dropping the hypochlorite dose; last time I dosed with 0.3g/66L, this time only 0.18g/66L.
Gonna find that line and toe it.