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Three ways to improve your pond


Garden ponds provide fantasic wildlife habitats, but they can attract algae and pond weed. A small amount is beneficial to ponds, providing food for tadpoles and other water creatures, but too much can block light from submerged plants and prevent them from photosynthesising - reducing oxygen levels in your pond. Follow our tips to help keep your pond water clear and free from algae.

How to do it


Oxygenate the pond. Plants such as hornwort and elodea, which sit below the surface will add oxygen to improve water quality.


Add barley straw. Barley straw limits algal growth by absorbing excess nitrogen. Remove straw after six months, or when it has turned black.


Condition the water. If you top up your pond with tap water, add a conditioner to remove chlorine and minimise algae.

Discuss this project

Talkback: Three ways to improve your pond
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patzz 01/05/2014 at 19:31

Blanket weed. Help, how does everyone keep it down or better still out

pansyface 01/05/2014 at 19:47

I think that there are proprietory liquids which can be added in dilution to ponds without injury to wildlife. I find with our small pond that a child's fishing net keeps it more or less in check. If you have frogspawn or toadspawn you will probably find that they eat some of it for you too.

Welshonion 02/05/2014 at 00:54

Barley straw.  If you don't know a farmer, they sell it in garden centres.

Dovefromabove 02/05/2014 at 05:52

Or you can buy a liquid made from barley straw.  It works really well. 

Clarington 02/05/2014 at 09:25

Unless your pond is *huge* (mine is 2,500 litres and not large enough) buy barley straw extract. You can get it easily enough online or at a garden centre.

There is an idea that you can put the barley straw itself into your pond - you can. But all the expert guides I've read say that this wont work (can't remember why - there was a good reason) unless you've a huge pond.

That said you noticed the extract working within 24 hours and repeated applications as prescribed seems to be keeping our pond crystal clear.

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