If you are running any kind of hydro, I would highly recommend you get rid of ANYTHING even remotely organic in your nutes or additives.
I recommend Jacks 321 Hydro formula if you can get it where you are. Another option is the MasterBlend line.
When I say “organic” I mean anything derived from plants or animals. You ONLY want pure salts for the mix.
The problem is any bacteria or algae will just love to grow when fed anything organically sourced. Those things will drive your PH up as they grow plus increase the potential for root rot, make for smelly water, slime, etc etc.
You mght also consider lowering your PH slightly and see how it goes. I find closer to 5.8 with a small up-wards drift works best in my setups.
I personally think your nute temp is fine. Once you hit much over 22C, any bacteria is far more likely to explode. Its a balancing act though. As mentioned above, lower temps will slow growth of roots as well as slowing the bacterial growth. I never go over 21-22 max in a situation like yours. Actually, in my current setup I try to keep the rez at more like 15C or lower, but I have a unique setup that isolates the rez from the roots. The roots themselves are held between 21-22C at all times.
Edit: My comments on PH assume you are using clay pellets/hydroton in your setup?
P.S. I love autos. Its all Im growing from now on.