Ornamental Fish Production and Management (1+1)

These are caused by tiny suspended algal cells causing green water, or beds of filamentous algae. They can be both unsightly and potentially dangerous for the fish. Like plants, the algae photosynthesise during the day so there is a net output of oxygen, although this ceases overnight when there may be a net uptake of oxygen as the algal material carries on respiring. In addition, the sudden die-back of an algal bloom can result in large amounts of rotting material in the pond and obvious pollution problems. Algal blooms are normally caused by a number of factors including too much sunlight, too few submerged plants, inadequate shading, over-feeding of the fish and fertilized run-off from the garden entering the pond after heavy rain. To control algal blooms CUSO₄ can be used.