Is chlorine much stronger then javex ?

I don't know anything about wells but I know this about chlorine:
Bleach is sodium hypochlorite, regular household bleach is around 5.25%
available chlorine, the stuff you get at the pool store is the same
ingredient but stronger at maybe 10 to 12% available chlorine. Calcium
hypochlorite from the pool store is about 65% to 75% available chlorine
per weight, lithium hypo is about 35%, and those chlorine pucks, aka
trichlor, are 45.76% available chlorine per weight (yes the label says
90% but). The stabilized granular chorine, aka dichlor, is 32.24%
available chlorine per weight (yes the label says 64% but.)

Sorry I can't help you with your well, though.