Frequently Asked Questions
Prevention
How can I prevent an algal bloom? - Algae need three things for optimal growth: light, nutrients and high temperatures. Lowering the nutrients, light and temperature available to the blue-green algae in the water supply will help reduce algal growth. The speed at which water is flowing and mixing is important in controlling light and nutrient availability to algal cells. Keeping livestock away from the farm dam or water supply; avoiding run-off into water supply from fertilizers and pesticides; taking some water treatment measures BEFORE bloom starts; and if practical - changing mixing patterns or covering the dam or water supply to screen out light may help.
How can I reduce the occurrence of HABs? - Reduce nutrient loading of local ponds and lakes by using only the recommended amounts of fertilizers and pesticides on your yard. Properly maintain your household septic system. Maintain a buffer of natural vegetation around ponds and lakes to filter incoming water.
Can I use chemicals to treat water with blue-green algae in it? _ Most chemicals work to PREVENT an algal bloom. Water in small dams can be protected from blue-green algae by dosing with gypsum and alum. These chemicals work by removing phosphorus from the water. Algaecides can be used to safeguard water for agricultural use in farm dams BEFORE algal blooms occur. However, if used to treat a bloom, the algaecide may cause a release of toxins into the water when it destroys the algae. Algaecides may be toxic to organisms that naturally control algal blooms or, if not correctly applied, to livestock and humans. Before using algaecides seek advice from the relevant authority.
