hello! i m developig c41 with colortec chromogen and bleach III kodak and the relative fixer, i don't use a stabilizer but use a COLOR PHOTOFLO made by Ornano BBC97 here in italy.
i have a sort of red flashing....not in all FRAMES but 2 or three.
Use the camera to be shot a roll film and use another tank or sent to lab, if red flashing once again, the camera should to be repair. Developing tank usually very reliable and if light can come in the tank, it should can lead serious leakage liquid when you reversing your tank at processing film.