Pond advice please

[fussymare]

We've had a wildlife pond in our garden for many years now. We've never had any problems maintaining it, and have healthy aquatic plants in baskets on the ledges around the edge. For some reason this Spring it has become really stagnant and smelly. Frogs always use it to breed, but this year none of the frog spawn has survived.

Is there anything I can use to treat the water? Whatever I use must be frog friendly, as lots of frogs are still inhabiting the pond. It doesn't smell unless you dredge stuff off the bottom (which we have been trying to do) but the water is quite green, and a bit "filmy" on top.

I've tried looking around on the internet, but it's a bit of a minefield out there! It's shaded for a large part of the day, and we don't have a fountain, pump or anything similar to keep the water moving.

[Totally Scrambled]

Hello Fussymare,
You could try barley straw in the water, I think aquatic stores stock it in pouches etc.
Here's a link to a sight picked at random
http://www.barleystraw.co.uk/
Dom

[SouthernDave]

What he said! I know they use straw in docks to prevent the water from going green and stagnant. I also wondered if a bit of a flush through with rain water from a barrel would help? My neighbour flushes his pond (aquatic) through fairly regularly to keep the water fresh.

[fussymare]

Thanks - we have used barley straw in previous years when it was just an algae problem, but this seems a bit more like the water going bad from all the sludge at the bottom.

I've had a bit of a dredge around with a net today, and thrown 2 bucketfuls of sludge and decaying twigs, leaves, etc on to the compost heap. I've also chucked out some of the water to try to reduce the level a bit. This should make dredging easier.

The actual water isn't that green now I've seen it in a bucket. It looks quite clear. Well it did until I started to stir up the bottom of the pond.

It's a little bit pongy, but not really bad. So I might just keep on with dredging and taking out some water over the next few days, then refill, pop in some barley straw, and wait for it to all settle down. I heard that if you refill with a hose held high up this helps to oxygenate the water.

Fingers crossed!

[Freelander]

Hi fussymare
Natural ponds require a certain amount of silt in the bottom to help amphibians and insects breed and survive the winter, although too much silt will cause toxic gases to build up to a level whereby the water becomes stagnent. I know alot of fish keepers who use a specialised pond aqua vacs that will remove as much or as little silt as you wish, these vac can be hired or bought cheaply on second hand web sites, or even better borrowed for someone. As stated barley straw will help remove algae and a partial 25% water exchange every few weeks will help keep the water healthy, best to use recycled rain water to avoid chloride etc from tap water which will be harmful to the echo system in an exsisting pond. If its possible the pond will benifit from some form of waterfall or oxyinator to help break the water surface allowing the build of gases to escape, if the position of the pond does not allow this introduce oxyinating plants such as Candian pondweed which release tiny air bubbles to maintain the oxygen content of the water. Hope this helps

[Steve the Gas]

Lynne P if you read this - could you post some of your pondweed over to me please?

My pond is green atm.