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Beware the dreaded green stuff


Hi All,

Just thought i would like to share my recent experience with all of you fish pond owners out there.

Over the past few weeks our pond has developed a very green look. Pea soup comes to mind.

This has obviously been due to the onslaught of the summer sun.

Our fish pond of course is out in the open and in a South facing garden so the sun is on the pond most of the day.

Anyway, the algae had been getting thicker and thicker by the day, so much so that we couldn’t see the fish swimming just below the surface.

Not being very well up on pond maintenance – (our last one didn’t need any as it was located in the shade) – i took advice from our local fish monger …. sorry …i mean fish shop ….

From their many products on the shelf, they suggested that we use something called Tetra Pond AlgoRem.

Well, i read the instructions thoroughly and mixed the contents as advised and poured it into the pond.

The mixture had the desired effect as it started to clear the colour of the water by the following morning.

Brilliant, i thought.

A couple of days went by and OH – who seems get up very early these days – came rushing into the bedroom at 5am ….. yes 5AM …!!!!!

Didn’t even know that time existed …..

“The fish are dead” she exclaimed in a tone of voice designed to wake me up.

Knowing by the tone in her voice that she was expecting instant response, i jumped out of bed and headed straight for the pond.

Sure enough …. floating on the surface there was one dead fish….

I gave her my “You got me out of bed at this time of the morning for one dead fish” look and headed straight for the kettle.

I always work better on a cup of tea.

I sent a text to friend of ours who is a pond maintenance person expecting to get a response during the course of the day.

He must have heard OH shouting at me because i got a response straight away.

He suggested that the algae, although treated, dying back and sinking to the bottom of the pond was also taking all of the spare oxygen from the water and starving the fish of their life blood.

He suggested that a change of water and a good clean up would probably do the trick.

By 6 am i had the pump in the water and the guttering in place to make a water run to the drain and started emptying the pond.

Bear in mind that i do have a full time daytime job and hadn’t given this a thought.

By 8:15 the pond was almost empty …. yes, it’s a pretty powerful pump to shift nearly 2,000 gallons in a couple of hours …..

I phoned work and told them what had happened and luckily they were quite ok with it and said try to get in by lunch time.

So i set to with the jet wash and gave the pond walls a good clean and shifted all of the dead muck and fish pooh out of the bottom of the pond.

By 10:am i was filling the pond up with clean water.

At this point i thought i might as well change the UV light as well so rushed off into town to get a new one.

So now my troubles began ……

On attempting to remove the old tube from the filter box, the glass tube that it fits into broke just on the end.

This meant that i now didn’t have a waterproof unit.

I looked on the internet to find a new tube and fortunately spoke to a company that said they had one and could dispatch it that day for me to receive it on the next working day.

Great … OH had a hospital appointment the next morning which meant she was out when the postman called.

When she returned there was card saying allow 24 hours before trying to collect…

Anyway back to pond filling.

After a couple of hours of filling the pond was reasonably full so i added the desired amount of chlorination/ distress liquid and eventually put the fish back.

There is nothing like a clean pond to appreciate your fish.

So, back to the the filter …..

Having collected the package from the post office sorting depot i presented the glass tube to the filter casing ….

Too big … didn’t fit … phone call to company ….

“Sorry sir, that model was discontinued so we sent you the replacement for that model …”

Words failed me.

I grabbed OH and we set off for the World of Water centre that sold us the filter boxs in the first place.

I advised them … politely of course …. that they had sold me something that was discontinued and that it was their responsibility to supply me with a replacement part..

My tongue was bit in cheek at that point, but if you don’t ask – you don’t get …

After about half an hour of to-ing and fro-ing they eventually came back with a glass tube in their hand which just happened to fit my UV casing..

and joy of joy they only charged me £14 for something that i know should have cost around £25 from my conversation with Oase.

So, home we went and after an hour of making sure that electricity and water could mix satisfactorily the filter box was in perfect working order.

So now when i look out of our loft bedroom window we can see the fish in the water …. just …

So you can see from this photo that i have now finished the pond area apart from the edging slabs and i have also finished laying the path to the top of the garden …. this being completed in a 103 degree temperature on Sunday afternoon …..

I did however take a break to watch the Grand Prix and the tennis – well done Murray ….

By the way did you notice the beautiful pale green tree in the 2nd photo in next doors garden.

She is an elderly Indian lady and the tree is from her home …. at this time of year it looks magnificent and yet so delicate ….

Now, i just want to sit back and enjoy the garden …… but wait …..

I see some weeding that needs doing …. and oh yes……. there’s the shade to erect for the fish pond so that the sun can be kept off it and my fish can swim in peace…

So that’s tonight’s job …..

Catch you all later …..

More blog posts by tony1247

Previous post: The Fruits of our Labours

Next post: Progress in the garden - The new pond rockery



Hope you get that shade on soon. Thats the cause of the trouble. I only have a small pond, but when the Council
took away our rubbish boxes and gave us new Blue
wheelie bins, I grabbed the old lids and kept them. Ideal for just laying across my pond. I kept one box to mix
compost in.
Incidentally the new Blue Bins are Jaques Mazorelle blue !
(? spelling)
The Council workmen said they have 40,000 new Blue
wheelie bins to deliver in the Borough and it will take 10 years !

8 Jul, 2013


this is a good blog Tony, what a day you had! What understanding bosses you must have too [unless you run the company?!] Your garden looks so perfect, not a weed in sight, and a very interesting use of a narrow-ish back garden, it seems broader for the hard landscaping doesn't it?The pond itself looks spectacular, it must have been difficult to create.Poor old fish, but you sorted them out in the end and now have a very clean pond, I guess next time you know to take the fish out before you use the pond cleaner[but WHERE do you put such large fish?]Did you feel a bit Victor Meldrew at the aquatic centre demanding your rights? LOL

8 Jul, 2013


Had you thought of using water lilies to produce some shading? There are varieties to suit various sizes and depths of pond .Your local water garden (if you have one) would be able to advise you on a good choice. Also lots of Goy members have ponds with lilies.

8 Jul, 2013


Thats a good idea Stera, we have a koi pond......koi eat all the plants......and can be seen grazing the algae on the walls of the pond, even though the house faces south and the pond is in the garden behind it, it gets the morning sun and even with complicated filters that they backwash. ?? regularly and a lot of aeration it still goes green in the summer.
Oxygen in the water is a key to healthy fish I think........and skimming with a fine net can help too

9 Jul, 2013


Hi Guys
Thanks for all your comments.
We do have some lillies in the pond but they are very new and very small.
As of this morning there is a tarpaulin hanging over the pond. I used a pulley system to hang it on the inside underneath as i want to grow stuff over the top.
If it rains i can tilt it to get rid of the water and in the heat of the sun we can lower it to give more shade.
Not just a pretty face you know.
Unfortunately our pond is in full sun all day and currently that is around 28/30 degrees. Thats one of the reasons for the pergola so hopefully by next year we will have some plant shade over the top.
The clematis montana is growing nicely up the front pole and so is the wisteria on the centre pole.

9 Jul, 2013


Good news. Any crisis problems gardening, the motto is
'Dont panic ' Do as someone said - have a long, hard,

9 Jul, 2013


Excellent blog Tony........can't wait for your next fishy tale!!!!

9 Jul, 2013


There may be a problem with the things you are going to grow over the top as when they lose their leaves in autumn they will all drop into the water, which you don't want. Many pond owners put fine netting over their ponds in autumn to prevent this
If you have planted the right lilies for the size of the pond the problem should disappear as they mature. You can get a free booklet (I think its free anyway) from English Nature that tells you lots of useful stuff about planting for wildlife(ISBN 1857168569 )and there are usually books in the library with hints about panting, proportion of shade to open water etc. You can save yourself a lot of work later by getting the balance right to start with.

9 Jul, 2013


Steregram - many thanks for your input. We do already have a net over the pond - we suffer with the Heron - so leaves etc aren't really a problem. We have had a pond previously so are aware of the water problems but our last pond was well shaded whereas this one is in full sun all day long.
I have now erected a shade tarpaulin which is going to help but i have already realised that it needs to be bigger and lower .... so more work for this weekend.

10 Jul, 2013

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