Pond Algae

[pondsaregreat]

Hi,
I have a pond approx. 12' by 6' and @ 4' deep in full sunlight and no over hanging trees nor does it have any water plants. Up to last year it was quite clear and was stocked with 12 medium size goldfish, assorted newts and water insects. Then last summer the water turned green with algae and the fish disappeared (I blamed the heron that has been hanging around). This spring the water has taken on a brown muddy colour and there are about 50 1/2 inch goldfish swiming about seemingly unstressed by all the algae.
Does anybody have suggestions to how I can cut down the amount of algea and what plants could be used to address the problem?

[Jonny]

The algae grows because of the amount of light getting to it and also because the water has nutrients in it. What you need to do is to put in some plants that will use up the nutrients, putting in some (untreated) barley straw can help, and a filter with uv will work. Running the water through a magnet is also supposed to help. You can also use chemicals, but be careful if you do as you may kill the other plants or the fish or other wildlife.
Personally I found the filter box with a uv attachment the best thing to use, but you do have to clean it regulary....................Jon

[pondsaregreat]

Thanks Jon,

I'll give the barley a go and bung some plants in.

Cheers

[tomarg06]

Hi. My pond has gone muddy this year for the first time. We successfully bred goldfish last year. No idea where the mud can be coming from, but when I clean the filter it definitely looks like mud not silt. Ideas of how to clear it, anyone, please?

[John]

I would love to know the answers to good pond management. If you can tell me where I am going wrong I would be greatfull.

My pond is about 10' by 7' one end and about 4' the other. The depth goes from 3' down to 4'. I have various water plants around the edge plus I have two pumps, one that goes to a filter box with an UV light and the other to a fish mate filter system. I have built a waterfall and a stream running into it and the second pump also runs a fountain system (allthough I don't have it as a straightforward fountain, more a plume of water straight out of a pipe). This way there should be plenty of air in the water. I regularly treat it with a liquid form of barley straw.

I have one large fish (probably weighs around 3lb) and another 10 that are medium size (about 6 to 9" in length) we also have about 20 very young (from last year, all about an inch or two in length).

I have been having major problems with blanket weed plus the water discolours very quickly. I also get a fair amount of a small worm like creatures (maybe Anchor Worm but I'm not sure). It got so bad this year that last Saturday I had to get all the fish out of the pond and put them into our bath. I then emptied the pond and actually power washed the butyl liner both in the pond and also the stream and waterfall. Both filters and pumps were thoroughly washed out and then fresh water (treated with a sachet of Interpet Bio Start, Fresh Start and the required amount of liquid Barley Straw) was hosed back into the pond.

Once the pond was filled I started the pumps and boxes back up and left it like that overnight before introducing the fish back in on the Sunday. By morning (before the introduction of the fish) the water had already discoloured a bit. Since the introduction the water has coloured quite a bit already (dirty brownish).

I am now waiting to see how long it takes for the worm and blanket weed to return.

I had these problems all through last year as well as this one. I have emptied and cleaned the pond on at least 4 occasions, always treating the fresh water before reintroducing the fish).

What more can I do?

John

[eeyore]

Originally Posted by Jonny

The algae grows because of the amount of light getting to it and also because the water has nutrients in it. What you need to do is to put in some plants that will use up the nutrients, putting in some (untreated) barley straw can help, and a filter with uv will work. Running the water through a magnet is also supposed to help. You can also use chemicals, but be careful if you do as you may kill the other plants or the fish or other wildlife.
Personally I found the filter box with a uv attachment the best thing to use, but you do have to clean it regulary....................Jon

The magnet thing is unfortunately a con with no scientific validity (the same company sells magnets to put on your water pipes to descale them, and on fuel lines of cars to improve fuel efficiency - they are currently under investigation by trading standards.)

Barley straw should work well, but you need to float it in little sausages not use the liquid form (we do straw sausages on a grand scale for our lakes - which is fun). What happens here is that the barley decomposes giving off humic acids, which react with water and sunlight with 2cm of the water surface and forms low level hydrogen peroxide which bursts the cell walls of the algae. This needs to be sustained at a low level over a long period hence the sausages which is why just adding liquid HP doesnt work as well.

[John]

Originally Posted by eeyore

Barley straw should work well, but you need to float it in little sausages not use the liquid form (we do straw sausages on a grand scale for our lakes - which is fun). What happens here is that the barley decomposes giving off humic acids, which react with water and sunlight with 2cm of the water surface and forms low level hydrogen peroxide which bursts the cell walls of the algae. This needs to be sustained at a low level over a long period hence the sausages which is why just adding liquid HP doesnt work as well.

Thanks for that in eeyore

Where do we get these Straw Sausages as it is obvious, as you say, the liquid form isn't working.

John

[Chalk Downlanders]

Plant a Gunnera. that will quickly reduce the amount of sunlight hitting the water.

Kev

[nightshade]

find where the nutrients are coming from is it just fish poo or do you have run off from the garden,did you put plants in ordinary garden soil or the very low nutrient stuff?
Shade the pond with the green net garden centres use for shade loving plants the UV filter box works well

[John]

Originally Posted by nightshade

find where the nutrients are coming from is it just fish poo or do you have run off from the garden,did you put plants in ordinary garden soil or the very low nutrient stuff?
Shade the pond with the green net garden centres use for shade loving plants the UV filter box works well

The nutrients will be from fish poo as there is no run off from the garden. All the plants have been placed in Aquatic soil.

I was thinking of maybe getting a Gunnera as Sticky has suggested. I'm not sure about the net though. It possibly will do the job you state but I was hoping to keep the garden as a wild looking beautiful area and I think a net would spoil the look.

John