I would not worry too much about pathogens, especially in a system you are using for the first time. Normally, you notice by crop three or four whether you are going to get any. Best way to stop pathogens is sweep up dead leaves, keep humidity down outside your tent, and keep your nute solution around 21-22c.
You look as though you are keeping things tidy enough, I would not worry too much about things until you notice an issue. Main worry is Spider Mites. Learn to recognise and deal with those and you will mitigate the major headache with growing.
From the look of them, they need the PH adjusted and a huge dose of LITFA. Food in the water, water at 21-22c, PH adjusted. Nothing else...
Pathogens are restricted greatly at 21c, ideal temps for roots are between 22-24. Much colder than 21 and you will stunt growth from the nute solution being too cold.
Try staying closer to 70f than 69 (or 66!) and you will still be fine for pathogens, but you will not be stunting your plants. 71.5 is still fine, 75 is the top limit for vigorous growth and where you are just starting to have a greater risk of root rot etc.
so, 68 or less =ouch 69-70=low end 71-73 optimal 74-75 still fine but at the warm end 75 or more=ouch
If root rot concerns you, that is if you know you have had it in that system before, stay to the low end.
If you have not had root rot in that system before, either it is new or you have bleached+scrubbed it or similar, you could go as high as 73 regularly and have no concerns. You would pretty much have to manually introduce root rot to suffer from it the first time you use a system.
You are currently at 'ouch', which will limit nutrient uptake and if you go just a few degrees lower (more like 59 degrees) will stop the plants growing altogether.
Remember, half measures with tiny babies. Not full measures, or double measures.
90% measure=90% yield
100% measure=100% yield
105% measure=50% yield...
From the sounds of it, that pool shock stuff would be good for cleaning your system in-between crops.
That is the time for double measures, when there are no plants in it.
if you can reduce your pathogens to zero between crops, it is very unlikely that any pathogen will spread enough in a single cycle to become an issue.
Then you can relax and watch the flowers grow