What would bleach do in a septic system?
Kill all the microbes breaking down the stuff in there
A big no no. Bleach and antibacterial soap is bad for septic tanks. You will kill all the bacteria that eats up and dissolves the chunks. That’s why there’s RID-X which adds good bacteria and enzymes.
However, you can add a cup or two of bleach to a water well to kill nasties.