Could be a combination of things really. Temps should be in the low to mid 70's for optimal breeding results. Why do you add bleach to the water system? Never heard of doing that before. I use diluted bleach to clean but never used the wipes, are you using bleach full strength? Are you letting the tubs air out?

How old were the rats that you started with? Could of died of old age? I've been breeding rats for about 2 years and produced easily 6,000+ rats. I breed mine on kiln dried pine and keep my temps in the mid to upper 70's and have never had any problems like you describe. The hairless is a dumbo (not a rex) and the black looks like a self.