How to Kill Blanketweed
- 1). Use a skimmer net to remove as much of the blanketweed as you can.
- 2). Install the proper filtration equipment appropriate for your pond. Consult the manufacturer to make sure that your equipment is suitable for your size of pond. Without proper filtration, nitrate and phosphate levels will become unhealthy for your fish.
- 3). Add a pond treatment that's advertised to reduce nitrates and phosphates in your pond. Use the amount recommended by the manufacturer.
- 4). Add barley straw to your pond, available from area farmers. This is a natural algaecide. Other commercial algaecides may be more effective, but barley straw extract is often the active ingredient. Several choices are available online.
- 5). Shade your pond from sunlight. Plant shade trees near your pond to reduce the amount of sunlight that reaches your pond. Construct a pergola over a large portion of the pond, if possible. Conversely, you can locate any new ponds in already-shaded areas.
- 6). Introduce shading plants to your pond that will shade the water underneath, such as lily pads. Add vegetable dyes to your pond water, which also filter out sunlight and give your pond an aesthetically pleasing tint. These are available at many landscaping supply stores.
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