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From £8.49
  • Deprives duckweed of essential nutrients
  • Inhibits the Growth of Algae
  • Easy to Use

Pond Cristalclear Duckweed Control, controls the unsightly spread of duckweed in pond water. It works by reducing the duckweeds natural food source thus eliminating future growth and helping to keep your pond water free from duckweed. Use Duckweed Control regularly for a cleaner pond.

When best to use ? use throughout the year and especially early spring onwards to keep the nutrient level low from breakdown of plants and leaves over winter - this leads to a cleaner pond too..


250ml Treats 4550 Litres/1000 Gallons

Winner of the 2010 PATS Retailers Choice Award for
"Best Water Gardening Product"

Available in the following variations:



1 litre

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* Always follow the instructions on the label. This calculator is intended to be used only as a guide to how much product you need to buy to treat your system. It does not take account of displacement caused by shelves, rocks and ornaments etc. and does not include the volume of any external filtration system. NT Laboratories Ltd. will not accept any responsibility for inaccuracies or misuse of this guide.

Product Tips & Advice

Tips for helping control of Duckweed :

maintain some movement of water in stagnant areas - this is always where duckweed gets a foothold and can smother the pond.

Crystalclear is not a herbicide it is natural bacteria and enzymes and will eat the waste in the pond that generates the nutrient for dreaded duckweed.

Keep that nutrient  down by making sure in autumn you pull out dying plants or falling leaves - heaps of nutrients going in may mean a tall order for the Cristalclear - but good maintenance will help this product work well.