Very useful as a disinfectant, it kills all things except some viruses (alcohol kills those). This fact emerged from the HIV crisis when bleach and needles were provided. The rate of HIV went down but the rate of Hepatitis went up because bleach does not kill the HEP-C virus, alcohol does however. "there is some evidence that bleach can inactivate (or kill) hepatitis C in syringes in laboratory settings, in real life settings it has not been shown to prevent the transmission of hepatitis C." and "The use of bleach to clean needles and syringes as a HIV or hepatitis C prevention strategy is not recognized by the World Health Organization, the Public Health Agency of Canada or Canada’s Best Practice Recommendations for Canadian Harm Reduction Programs (Part 2, released in 2015)." - Ref
Of limited use controlling algae as a disinfectant when used as a 7 minute dip in 1:20 dilution, but it does set back plant growth fairly substantially. By the time the plant has recovered from that algae will have set in again. You have to control the growth of the algae and by doing that it obviates the need for a bleach dip,a trend that came and went on the 1990. Paul Kumbholz popularized the idea, and fair enough, it worked of him. I spent years fiddling with it and found it pointless.
