where does inorganic waste go to after the treatment?

Algi bloom can also be called as eautrophcation and is caused by exess of chemicals added into the water flowing in slow mowing steams and ponds.This is very harmfull for the other aquatic creatures because this favours algal growth and this algae consumes a lot of oxegen in water thus reducing oxygen contents in water and all this makes the aquatic animal and plant to compete for oxygen thus killing most of the creatures die due to lack of nutrients in water.