Types

• Numerous species of algae can arise in a water garden, but most often it's free-floating algae that cloud the water and turn it green. These algae prosper in sunny, warm water that is rich in dissolved minerals already present in the water, or that build up in the pond from the wastes of fish or amphibians. Hair or filament algae grow into threadlike, cottony masses in water and can be more problematic. Pond slime coats submerged items in a water garden.