Chlorine as Algae Killer

Can somebody specify exactly what is in "Chlorine", i.e. what chemical(s) goes into their
local chlorine bleach product and the corresponding dilution / dip time for algae kill-off.

Here in Norway the most common product is kalled "Klorin" and I believe the label says
it contains a Hypochlorite? solution, can't remember the strength off the top of my head.

Used this in a 10:1 dilution / 2 minute dip to kill off plant algae recently.

Vals turned gooey after about 24 hours, swords looked like the *may* survive if given
lots of time and patience. Hygros looks OK.