Colombo Algadrex 500ml 1L 2.5L Garden Pond Green Water Algae Clarifier Remover

You need to ensure the Carbonate Hardness (KH) is at least 6. Once your green water has cleared, regular use of Colombo Bi-clear will help keep your water clear and healthy. The coagulated algae float on the surface of your water, sink to bottom or will be collected in your pond filter.

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