There are some algaecides available that can be used in potable water tanks and some are safe for use in waters that are used for irrigation of edible crops. Certain algaecides are even safe for fish. Always read the label of any product you are using to ensure you are using it correclty and for the purpose it was designed for.
Diquat is a contact herbicide that controls Spirogyra filementous algae.
Diquat is only slightly toxic to fish and if you follow the recommended application rate is followed, you reduce the possibility of harming aquatic life. However, as the aquatic weeds decay, the oxygen level in the pond water begins to deplete. Without the proper oxygen levels, fish may not survive. Using strip applications of diquat will help prevent harm to fish.
DiquatE-PRO
Use at a rate of 1 gallon per surface acre (4' deep)
Diquat Dibromide 37.3%. This concentrated Herbicide is for weed/algae control in and around ponds, lakes, commercial greenhouses and nurseries, landscapes, industrial land, recreational land, residential lawns, and public areas.
Over-dosing with algaecides can be a problem so do not attempt to erradicate a problem by simply adding as much as possible; always dose your tank or pond according to the manufacturers instructions.
We have a range of herbicides and algecides available in our store. See our range of algaecide products here.
We mainly deal in algae control products for ponds and lakes but if you require firther details on specific applications including water tanks please contact us directly by email.