Question

Why does water covered with excessive algal growth become polluted?

Answer 1

Due to the excessive growth of algae water contains a lot of phosphate due to the inflow of the fertilizers from the surroundings. The decomposition of algae leads to the bad smell and taste and even makes it unfit for drinking, bathing, washing, swimming, boating etc. and concentration of dissolved oxygen also decreases which may be harmful for aquatic life.