Bioguard Optimizer looks like it is regularly used in swimming pools as a remedy for algae. The only site I found listing potassium tetraborate does not show that it is used for swimming pools, and also that it is toxic.
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A: The product from Bioguard "optimizer" is not a product available in California so it must be very hazardous to the environment etc. I would not want to use a product in my pool that was that hazardous to people or animals. Use with great caution!!!. Or find an alternative like yellow treat or yellow out. Both good algae killers. Follow the manufacturer's label instructions.