Interesting.

The facts as they presented.

Pond, green water, pump and UV

The pond holds roughly 2,200 gallons, the UV has a capacity for a pond up to 4500 gallons, the pump can pump about 1700 gallons/ hour.

So it should work, but it doesn't.


Now the "Oh dear" bits.

First of all pond filter media (and sponges) should NEVER be washed with a hose. (Tap water kills the friendly bacteria)

The pond is too shallow for koi if it is 2feet deep.

There appears to be no bottom drain (a good idea if a pond has fish)

The pump should be as far away from the filter as possible. (So that it circulates all the pond water, not just the water falling from the filter outlet.

Adding chemicals to "see if it works" is a waste of money, since you have to add the correct amount / pond volume, and is only a cure for the condition, not the cause.


Now the good bits

Change or clean the quartz sleeve on the UV (They get covered in lime scale and don't work. (Like trying to see who is on the other side of a dirty window, you know something is there but you cant see what / who)

Buy some new filter sponges (They only generally last 2 - 3 years)

Buy some more filter media. That filter looks almost empty. The filter media you had is the "funny black short tubes" sitting on the filter area floor. Your filter should be around 1/3 - 1/2 full of these. (Other filter media is available) These are for the good bacteria to grow on and multiply.

Take the pump out and make sure it is clean.

Buy a paddling pool (argos have them for £10. Other suppliers are available)

Pump all the pond water out (The flowers will love it) save some for the paddling pool. As the pond empties put the fish strait into the now filled paddling pool.

Clean the pond out. Over the years it will build up with sludge and all sorts of nasty stuff. Ponds should ideally be cleaned once / year. But those with bottom drains don't since a bottom drain does all the hard work.

When its all cleaned take pictures.

Re fill with tap water, and add a dechlorinator / pond conditioner.
Start the pump and add a couple of small fish.

Do not feed the fish in the paddling pool.

After a couple of weeks add the remaining fish. However if there are "a lot of fish" it would be wise to give the bigger ones away.

Since you know little of ponds, you may also like to read the following.

Koi ponds

Green water

UV and bio filter

I wish you good luck.

Quote:

Think you will find it does make a difference.

I get emails with pictures, or so the sender thinks. They have attached pictures that are not on the desktop, so you end up with a long description of where the picture is, but no picture. Put the picture on the desktop, then attach it, works every time. (But I don't know why) Perhaps Admin knows?

In order to work some things out, I need to know the pond volume. Can you measure it again please, stating how long each coloured bit is starting at red and going clockwise

Red
Blue
Lime
Yellow
Cerease
Dark green
Orange
Pale blue
Brown
Navy

The more accurate the more precise I can be (Only have to do it once)

Also, I must know the depth (without this, its pointless)

Another question.

How often does your uncle turn the pump on?

Can you take a picture of how the water gets back into the pond from the filter? (You can see it, I can't) I guess its via a waterfall?

Attach file:

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  pond.jpg (44.07 KB)

A few questions.
1)What are the pond dimensions?
2)What pump has it got?
3)How old is it?
4)Has the pond ever been "maintained"
5)Is the filter over at the back? (Looking at the dark square at the far end in the first picture)
6)What fish are in the pond?
7)What do you call "a proper filter unit" ?
8)Nice pond.

Its up to you.

If you want, and have the money you could buy a new pump.
You could also buy / make a diverter so the water going to the filter is reduced.
You could even drill a hole in the pipe (NOT the pump) If you do this, make a small hole first, then increase the size, if you start with a big hole you can't make it smaller. This method does work although it can be a pain taking out the pump all the time to make the hole slightly bigger, this is where a diverter saves time.

According to the makers website Your pump can pump 5500 litres / hour. Even at 1m head it pumps 4500 LPH.

The information about the filter clearly says:
"The entire pond volume should pass through the Bioforce every 1½ - 3 hours."

You said

Quote:

Do you see what the problem is?

Damn, no more cafe lunch.

I think the organisers missed the elephant in the room on that one.

The marks do seem to be indentations as opposed to extrusions.

Heron would be a good guess, but the only way to know for sure is to set a camera with video recording facility to watch, but since that is impractical and will only identify the cause
I can only suggest you cover the pond with a net, pegged down at regular intervals.

You could always give it a spring clean.

Pump all the water out clean the liner, keep the sludge next to the pond for a couple of days (In case you scooped up a small creature) Then refill, add de-chlorinator etc and refill.

Obviously you do this after you have brought your new bigger filter and pump.

Recommendations for pump and filter? down to personal choice, I may like brand "A" but you may not feel comfortable with it, so its down to personal choice.

If you look to the right on this forum there is a volume calculator.
Using your figures (450 cm x 300cm x 70cm) You will see that you end up with a volume of 9450 litres.

If you then use a search engine to find the filter you mention the figures show it is suitable for a pond that is size: 625 - 2500 Litres

So if your figures are correct the filter is nearly 4 times too small.