Water Treatments | Algaecides

Polidex / Polypro Algaecide
CyanobacteriaString algaePolydex Algaecide

Polydex & Polypro Algaecide

For major problems of algae blooms in drinking water basins or private ponds, you can consider Polypro or Polydex, bacteriostatic algaecides which do not precipitate or stratify as copper sulfate. Canadianpond.ca is certified to sell and apply these algaecides in Canada under certain conditions. Clients require a licence to purchase pesticides in order to buy from us. Farmers can purchase from us with proof of an E certificate.

Contact us for details and to order.

Technical specifications

You can use Polypro for residential and commercial ponds and Polydex for projects requiring NSF certificate (see information below).

Certified application of algaecide to treat blue green algae.

An Algaecide is a water management tool to be used responsibly by pond owners or water managers where persistent or toxic algae blooms are present. Polypro is considered a last resort treatment for pond owners and water managers, when aeration, beneficial bacteria and watershed management are not sufficient.

Polypro is a strong algicide for ponds. Use with extreme care, following dilution instructions and analysing water before reapplying. This product can be toxic to fish, especially for Koi, goldfish and salmonids.

Water testing prior to re-application is required. Read all product labels carefully. This product is for the private pond (closed pond systems) use only. Other use will require approval by regulatory agencies. Contact us for more information on when, where and how to use this product safely and responsibly. Ultimately the end user is responsible for the proper application of this product. Regulations for sale, purchase and application differ may by province and municipality. Inform yourself regarding what is permitted in your province.

To sell Polypro and Polydex in Quebec Canadianpond.ca needs to see your Category C or Category D permit. If you do not have this, we can help. Contact us for details concerning our application service by our trained team of technicians.

Cyanobacteria in a pond can be treated with Polydex-Polypro

Polypro, algaecide for ponds and basins

  • Algaecide for closed pond systems only. This product should never leave your pond to reach streams or other water surface systems around the treated pond.
  • This product is toxic to algae in your pond. It is also toxic for fish and invertebrate species. Use with extreme care, following dilution and application instructions including analysis of the water before reapplying.
  • For ponds with persistent or toxic algae blooms, where other treatments, including aeration and bacteria based treatments, have been unsuccessful.

Notes for treatment

  • Follow all instructions and procedures on the label and from your pesticide training courses.
  • Wear long sleeves, long pants, gloves and protective eye wear during the treatment.
  • Dilute algaecide with pond water (4 to 10 times) in a bucket. Spray directly on the water surface, especially where the algae are growing. Do not treat the pond on windy days.
  • Post a sign to warn pond users to allow a 24 hour period before bathing or allowing animals to use the pond, after a treatment.
  • Always test the water before reapplying the product on the pond. A swimming pool copper test kit will suffice, simply follow the instructions. If copper is present, there is no need to reapply the algaecide.
  • If possible remove dead and floating algae from the pond surface after the treatment, so it does not contribute to more organic decaying matter, which will continue to provide food for algae growth.
  • Take care during application, as non-target plants will suffer contact burn if undiluted algaecide comes in contact with them. Avoid contact with grass, ornamentals and other foliage.

*Note: The use of copper sulphate algaecide has a potential for detrimental environmental effects if not used properly and in higher concentration can be toxic to fish and other organisms. Overuse of this product can result in a copper build-up in the sediments leading to a sterile bottom, killing important beneficial bacteria, microorganisms, snails and other beneficial “creatures”. Ensure proper aeration and regular application of beneficial bacteria in your pond to help prevent the reappearance of algae along with other measures that will help shade the water such as a blue or black dye, floating islands, nympheas etc.


For algae control:

  • In ponds with fish, apply 1.7 ml / m² ( Koi and Goldfish Hardness more than 75+ )
  • In ponds without fish apply 3.3 ml / m²

For contaminated water (E-colis, cyanobacteria…):

  • Apply 4.3 ml/m2

If you have any doubt, call us so we can give you advice on the correct dosage.

Available formats

  • 1 litre
  • 4 litre
  • 10 litre (contact us)
  • 208 litre (contact us)


Polypro is absorbed by the algae or unbeneficial bacteria. The copper ions that they contain interfere with natural metabolic processes, such as membrane permeability, respiration, digestion, reproduction, and even denaturing of DNA. As a result, algae die from their own inability to perform biological functions. Algaecide must be applied at a dose of 0.2 ppm copper equivalent, which represents a dilution of 1/300 000 (Polypro volume/water volume). When the algae are under control, keep a low dose of about 0.10 ppm and it will not return.

  • Polypro kills Escherichia coli; zero C.F.U. (colony forming units) after 1/2 day of exposure.
  • Polypro kills Streptococcus faecalis; zero C.F.U. (colony forming units) after 2 days of exposure.

Polydex and Polypro products are a highly biologically active ionized mineral matrix, which effectively stabilizes copper ions [Cu(H2O)6]2+ and disperses them evenly throughout the water. The advantage of using Polydex or Polypro that gives a high copper ion concentrations are:

  • Lower required doses
  • Higher efficacy
  • Most biologically active form
  • Works in a range of water conditions
  • Greater concentrations of ions

Polydex or Polypro algaecides are strongly hydrophilic in nature. Therefore, they disperse quickly in clean water (~6 meters/hr in all directions). Once well mixed in the water, this product stays highly stable throughout the water body, regardless of seasonal temperatures or water conditions.

What can you expect of Polypro algaecide

In ponds where there is an existing algal bloom, expect to use Polypro in proportion to the biochemical demand for copper needed to kill the bloom and clarify the water. After applying the algaecide, algae at the surface may appear brown – and may exhibit a foaming activity as resident bacteria digest the dead algae. This is short lived and the water should clear in a matter of days. In clear water, there will be no visual change and, when properly maintained, the water will remain free from algae.

Application method when dosing from a boat

For this method, it is important to stay upstream of the direction of the wind so that it can push the product towards the middle of the lake and not the opposite. Start treatment from the bank and continue to release the product over the third or half the surface of the water. In larger lakes, it is recommended to release the product in parallel lines of 20 to 100 feet (6 to 30 meters). Do not treat on windy days.

Polydex with NSF Certification

Polydex is a bacteriostatic algicide like Polypro. It controls algae blooms and unbeneficial bacteria in water basins like rainwater retention tanks, leachate treatment basins, sewage pits, municipal drinking water tanks, golf club ponds, ornamental ponds, etc. Find out more about Polydex in our article About Polydex.

Available in 4, 10 or 208 litres formats (please call us). Polydex is designed and certified especially for use in municipal drinking water sources. It is important to follow the prescribed dosage to avoid a danger of contamination to human, fauna and flora.

Note: Some algaecide products that contain copper require a municipal permit before its use. It is recommended to check with your municipality before its use.