duck weed

[wendyl]

Can anyone offer any advice regarding elimination of duckweed on pond. Pond is open to sun has lots of plants and 3 large koi and about other smaller fish and has filter pump fountain and ultra violet. A garden expert recommend clarisan which I understand is only available commercially and taken off general market some years ago. Skimming is difficult because it collects around the plants- perhaps you can recommend a tool that works better than a small net???

[andyjevs]

I had exactly the same problem on my small koi pond. I tried the netting thing but as the pond was planted, the little duckweed got into every nook and cranny. In the end, i took evasive action. I bought a paddling pool, put the fish in there, threw all the plants and lillies and marginals away, emptied the pond and relined it. I then put new plants back in and re introduced the fish....no more duckweed !!!! Drastic i know but it worked. Other than that, you'll have to keep netting every little leaf out.

[maggie01]

you can buy a product that is supposed to draw it into lumps that sink to the bottom. I bought some for mine early in the year and then I vacuumed the pond. Haven't had any for a while. If you go to your store that sells pond products, they will tell you what to use.

[maggie01]

sorry got that wrong that was for green water algae.Been a long day.

[wendyl]

The pond is about 3 x 4 metres and brick and concrete not abtyl liner. The last time we emptied it we were unable to catch the fish until almost empty and to replace the water is an expensive process on a water metre. We do not have a problem with green water or blanket weed thanks to each of you but other suggestions welcome.