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Back Up 2 | 23050BIO

Back Up 2 | 23050BIO

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BioGuard Back Up 2 Algaecide is the most reliable algae preventative available from BioGuard. Its advanced formula provides protection against a broad array of algae growth. It won't dissipate in sunlight and it is effective in higher temperatures, when algae are most active. Its powerful surfactant/wetting agent penetrates even the smallest cracks and crevices, making it a near-impenetrable barrier. Additionally, it causes no pH level shifts, and is non-staining.


Pre-Treatment Checklist:

  1. Ensure all pool equipment is working properly. Clean or backwash the filter following manufacturer’s directions.
  2. Adjust stabilizer levels to 30-50 ppm by adding stabilizer.
  3. Check water alkalinity, pH, and calcium hardness with a test kit or test strip. Adjust alkalinity to 80-125 for plaster pools, 125-150 ppm for vinyl or fiberglass pools by adding an alkalinity increaser. Adjust pH to 7.2-7.8 by adding a pH decreaser to lower the pH, or by adding a pH Increaser to raise pH. Adjust calcium hardness to 200-275 ppm for plaster pools, and 175-225 ppm for vinyl or fiberglass pools by adding a calcium hardness increaser.
  4. Check and adjust residual chlorine level to desirable range of 1-4 ppm.

    This product is effective in controlling algae growth of both green and black algae.
  • Add this product directly to the pool by pouring around the outside perimeter of the pool while filter and pump are in operation.
  • Wait at least 15 minutes after application before entering pool.

Pools With Visible Algae:

If algae is visible, use 13.5 fl oz of this product per 10,000 gallons of pool water. After 24 hours clean out dead, settled algae. If algae is still present, repeat dosage if necessary.

Initial Application or When Pool Water is Changed:

Add 6 fl oz directly into pool per 10,000 gallons of water.

Booster Application:

Add an additional 1.5 fl oz per 10,000 gallons of pool water following heavy or prolonged rain showers and heavy bather loads.

Vacation Treatment:

Add 4 oz. of this product per 5,000 gallons for every week unattended. Pour product around the edges of the shallow end of the pool if shock is also being applied in the deep end of the pool.


Initial Application:
Add 6 fl oz per 10,000 gallons of water.

Ongoing Maintnance:
Add 1.5 fluid ounces of the product per 10,000 gallons of water every 5-7 days.


Dimethyl Benzyl
Ammonium Chloride

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