Hydra ST703 (Clear Filamentous Algae)
 Hydra ST703 (Clear Filamentous Algae)Hydra ST703 (Clear Filamentous Algae) 

Hydra ST703 (Clear Filamentous Algae)

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From:  £14.95(Inc. 20% VAT)(£12.46 Exc. VAT)

Brand:  HYDRA

  • Removes even the toughest of green filamentous algae and blanket weed
  • Absorbs the essential nutrients required for algae growth
  • Active ingredients ward off algae blanket weed long after the treatment
  • Shelf life 3 years, 1 kilo treats up to 20,000 litres

Features & Advantages

  • Hydra ST703 is effective upon more resilient forms of filamentous green algae.
  • Tough on algae but poses no danger to fish, birds, invertebrates, reptiles, animals, mammals, humans and water plants.
  • Works by feeding on the nutrients (phosphates and nitrates) that are important for the algae to grow.
  • Special product formula ensures residual effect which allows the continued action of Hydra ST703 long after the initial treatment.
  • No effect on biological filters
  • Available in easy to use powder form, that may be simply broadcast upon the affected surface.

How To Use

Usage Rate

  • 1 kg of Hydra ST703 treats 20,000 litres of water
  • 2x1 kg of Hydra ST703 treats 40,000 litres of water
  • 5 kg of Hydra ST703 treats 100,000 litres of water
  • 20 kg of Hydra ST703 treats 400,000 litres of water

Full instructions on the label.

Hydra ST703 quickly  eradicates the most stubborn algae strains by starving them. The results should be visible within 2 to 3 days.

  • Make a mixture of Hydra ST703 using pond water in water can. Pour the mixture evenly across the pond surface. The water may turn milky upon contact with the product. This is normal and the water clears up in few days.
  • You may also sprinkle the powder directly upon the algae to treat the highly infested area.
  • Repeat the treatment after 1 week at the same usage rate if some algae growth still remains in water.
  • For the product to be effective it is necessary that the water temperature is more than 12°C.


The Problem

Algae infestations are common in the water with excessive nutrients including nitrates and phosphates. Other conditions that support algae to thrive are abundant sunlight and warm weather. You would be able to clear filamentous algae of most types with popular algae treatment product available on the shelf; but some strains of algae are particularly difficult to get rid of. These stubborn forms of algae do not respond to common treatment products or procedures and retain their shape and colour even after the product application.  Some of the most difficult algae strains to treat are: Cladophoraglomerata, Enteromorpha Spirogyra, genus Charamacrophytic algae, Rhizoclonium and some varieties of blanket weed.

The Solution

Hydra ST703 is an outcome of the dedicated research efforts at ISO certified Hydra International Ltd. The product composition of Hydra ST703 includes a unique minerals and enzymes blend that rapidly starves off even the toughest algae. Hydra ST703 comes with an added advantage is its residual effect in the water which means that the product actively keeps off algae long after the initial application. Unlike most other products Hydra ST703 is effective even during cooler months of the year.


pdf Datasheet (Hydra ST-703) - Click here

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