Still the same treatment! as it seems to work. I make sure to keep it over 400ppm. I notice conductivity (the nutrients in the water) goes well up when I throw many slugs! No more water from the canal, since it rained enough. I have lots of mosquito larvae, so I try to give them everyday, to reduce the number of moskitos (they don't bite very hard and are really slow).
Cheers!
@goarilla, Thanks for the tip, it usually dries up (or gets absorbed) quite quickly, but I'll definitely pay lots of attention to it in the coming weeks. I'm even thinking to fit a transparent plastic bag over them if and when forecast seems too wet for too long.