Dodgy looking water in the pond!!!!

monvoy

Hi
Can anyone give me any help here? I've got a garden pond with some goldfish but the water has gone a very murky brown colour meaning I can only see about three or four inches beneath the surface. Also, if agitated, all this green 'stuff' which I presume is algae? comes to the surface. The plants in there ( if I could see them) water lillies, oxygenaters etc don't seem to be growing or flowering(lillies). The fish don't seem to mind though...does anyone have any suggestions......?
Ta very much.

10-10-20

Well, this is the bain of any pond owners life. Welcome to hell...

No, seriously, you can get chemicals to clear out the algae, it causes it to floculate (bunch together) and you then must remove the remains of the cells. The cause of the bloom is more than likely down to an overly sufficient supply of food (nitrates I think), either through dead leaves, soil in plant pots, through fish droppings or left-over fish food.

There is also a better approach and that is to use a UV filter either as a stand-alone unit or integrated into your pump/fountain. This kills the algae early on, and does not affect the fish.

So, start off by removing as much of the slime, leaves, dead plants and crud from the bottom of the pond to reduce the amount of food available to the algae; tightly control the amount of food that the fish are both eating and leaving behind (remove left-overs) and look at a UV filter.

The UV filters typically use only 6 watts of power, so aren't a major draw of power.

monvoy

Hey thanks for the reply.
I guess I must be putting too much food in for the fish, eh? As regards the plant pots, I do have some in there but I have gravel on top of the soil. What could I use instead of soil/compost???

10-10-20

The gravel won't prevent the nutrients from leaching out.
Ignore them for a while anyhow and think about UV!

crosstownk

Head to your local garden centre - you can buy pond treatment solutions that will sort it out for you. I had the same problem, but the treatments sorted it out in 6 weeks.

You should also have a decent proportion of floating oxygenating plants (about 40%). These will keep oxygen in the water and result in a clear pond. My pond is about 1 metre deep and I can see right to the bottom. At one stage I couldn't see beyond 20cm!!

EDIT : I have no UV, no filters and no fountain.

monvoy

Can you suggest any floating oxygenators?.....I'm a complete novice at all this gardening lark..!

crosstownk

monvoy wrote:

Can you suggest any floating oxygenators?.....I'm a complete novice at all this gardening lark..!

I've no idea of the name of the oxygenators I have but they look a bit like this. I got them in Newlands Garden Centre. They have a good selection of aquatic plants.

10-10-20

Make sure you get aquatic plants which are free from Blanket Weed.

Here's a good page...
http://www.swelluk.com/advice/blanketweed.html

Just out of interest, I had excellent surface cover of both floating oxygenators and also rooted plants and I still had major problems with algae. No matter what I tried I couldn't clear it. That's why I went down the UV route. I've since moved house, but my parents still have the pond and have a population of 4 goldfish (~5 years old - lost 6 to the heron) and also this year we got frogs for the first time, and we they aren't even near a lake or stream, but in the middle of Blackrock...

Oh, and another tip, put the pump on a timer so that it's not running at night in Autum. If it's left running it will cool the pond too much and a frost may kill any fish that you have in it. Turn it off and remove it during winter. Fish will retreat to the bottom and will be insulated by the water above as long as they aren't disturbed.

crosstownk

10-10-20 wrote:

this year we got frogs for the first time, and we they aren't even near a lake or stream,

Slightly OT, but did the frogs arrive by their own accord? I'm just wondering as my 3 yr old daughter is constantly asking 'when will the frogs be here'!

10-10-20

Yes they did!
A large frog got caught up and died in the netting above the pond early last year, and after that nothing much happened. But then around Feb/Mar this year a huge amount of frog-spawn appeared. Sure-enough, a lot of it hatched and was consumed by the fish, but recently my father heard and saw little frogs jumping around and looking quite content!
Before that we had water beatles (http://en.wikipedia.org/wiki/Water_beetle) which surface frequently to exchange the air under their shells...

Then there's the mosquito larvae and the silt/water worms....

Avns1s

You could also consider some mechanical aeration. Some form of fountain / spray system. This will also help to keep the water clean.