***The Pond Discussion Thread****

You may get green water initially. Tap water has nitrates in it, so it will often cause a bloom with sun due to the nitrates feeding the algae. It can be cleared simply by a chemical additive in the case of a small pond like this but it may come back. A UV clarifier doses the water passing through it with UV light to kill the green small algae (it doesn't stop blanket weed). However a natural pond will eventually reach an equilibrium.

It's worth learning about the nitrogen cycle: https://www.mankysanke.co.uk/html/good_water_guide__pt_15.html this should arm you with understanding about the nitrogen cycle so you can see how this will work with plants. Note that the may need nutrients added periodically if there's no animals in the pond (unlikely!)

Running water is good for a sound effect too in addition to moving the surface of the water to allow oxygenation.
I have found over the past few years that whilst the strong UV doesnt cure the blanket weed, it seems to definitely slow mine down, so it is easily controllable.....or is that just a placebo effect on me? lol
On replacing my UV's I discovered one of the locking nuts has perished (due to the UV weakening it most likely).
Managed to secure it for now (very slight leak, so not put the new UV in yet), ordered some new locking nuts and spares (with new O rings), should arrive Tuesday.
 
This morning from one end of the garden to the other here's a photo. The spawning brush, back wall and UVC return pipe (currently off) show the clarity:
an3WPVO.jpeg


After the mess I'd made yesterday, the drum had this back to being clear as a bell this morning. Gone were the little filaments of blanketweed from the spring clean, the particles of matter stirred up following having the drum on bypass due to motor failure.

Fish seem happy too.

I'll have a go at the frost damage (left side tiles) later this week.
 
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I was thinking of putting my spawning bushes back in at the w/e. Not sure I need to as the fish are flicking on lily baskets and Irises.
 
I was thinking of putting my spawning bushes back in at the w/e. Not sure I need to as the fish are flicking on lily baskets and Irises.

My pond is too deep for easy planting, my old pond used to be planted with irises, lillies etc.
Also the larger volume (14k litres) means it takes longer to warm up and cool so it delays them getting in the mood.
 
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Mines deep at one end (4.5ft) then has a slope towards the other end. Fish have been up and feeding for a few weeks. Water is quite warm as it washes over into a lower 'wildlife' pond via a stream. I bought the brushes last year when the pond was new, but too late for it to be used.
 
I am trying floating water cress this year.
A gent at work has been doing it the last couple of years, he set it off growing in a floating pot.
It grows fast an had overrun the pot and created a 3ft dustbin lid sized flaoting plate of water cress within a few weeks/couple of months.
His koi were spawning over the top of it, easily seen as they had crushed the cress in the process.
He then took out the floating cress and placed it in a tank in his shed, to hatch the spawn.
He got quite a few koi from it, not all survived but he placed quite a few back into his pond when they were big enough not to be eaten by the other koi.

Mine have never spawned (that I know of).
It is 6ft deep with no shelves around the edge.
22,000 litres so takes a while to heat up with the sun.
 
I am trying floating water cress this year.
A gent at work has been doing it the last couple of years, he set it off growing in a floating pot.
It grows fast an had overrun the pot and created a 3ft dustbin lid sized flaoting plate of water cress within a few weeks/couple of months.
His koi were spawning over the top of it, easily seen as they had crushed the cress in the process.
He then took out the floating cress and placed it in a tank in his shed, to hatch the spawn.
He got quite a few koi from it, not all survived but he placed quite a few back into his pond when they were big enough not to be eaten by the other koi.

Mine have never spawned (that I know of).
It is 6ft deep with no shelves around the edge.
22,000 litres so takes a while to heat up with the sun.


I use this, and I have since the old pond. It grows quick and can overrun the pond if not kept in check. It will end up taking some vertical space as the plant 'mat' becomes quite large too which can smother smaller plants or deeper plants. Bonus are the roots act like particulate brushes, but they also can be long and limit fish movement if the pond is too shallow. My advise is to don't be too light on pruning or cutting it back. I've had wheelie bins full of it. Good news is it does suck a lot of mess out of the pond.

I now use it on the large pond as it's floating (pond is 1.85m deep) and blocks a portion of the sun (but it will get matted with blanket weed).
 
Perfect, just what I am looking for then.
Never thought of trying it before.
No issue with the shallow depth as it is 6ft deep, I will prune it back well to keep it under control.
My koi will have spawned in previous years, but never had any luck with the brushes.
Hoping this will give me more success, as will hopefully be more visual when they do.
 
Rocks and a pump / waterfall of sorts added. I need to take a couple of larger rocks out at the shallow end on the right for smaller creatures to walk in & out. I also need to work on the water feature to keep the water in rather than spraying out to the sides - not sure how much I’m losing to wind gusts.

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The water is starting to clear but I need to add a chemical to sort the tap water. Is it just algae treatment I need? From searching, I’ve seen some things referring to chlorine but not sure if this is for the UK.

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Trying to figure out plants next.

A couple of my pond shelves are very shallow - just 3cm or so of water. Is this just too shallow for most marginal plants? They all seem to talk about needing 0-20cm of water above the crown, let alone from the bottom of the basket!

I was thinking:
  • UK frogbit floating in the middle
  • Crowsfoot in the deeper parts
  • Marginal:
    • Marsh Marigold
    • Yellow flag Iris
    • Blue flag Iris
    • Water mint
  • Some kind of grasses behind at the back
Thoughts on combination?

I’m unsure on quantities - I’m assuming I just want 3-5 plants of each type. The pond isn’t huge - about 2.5m long by 1-1.5m wide dependent on section. Any advice on this?
 
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The Irises I had sat under water and then shouted up and flowered above the water. Their roots can spread. They're happy up with water and even a decent depth.

One thing to note that a mature pond is likely too have a a mat of roots etc at the bottom, so after a couple of years you'll not be able to re-position them easily.

A Lilly pad is another option but it will need to be at the bottom and it will shade the rest of the water quite a bit. This helps reduce the water evaporation and reduce the heating of the water. You'll have new pond syndrome for a while - where all the water statistic vary for quite a while. Often you'll get great water (pea soup) but there's chemicals you can add to remove that, same with blanketweed (long strings of algae).

Lastly a shallow area will probably have cold temps and possibly be exposed in summer.
 
Tap water only needs treating if you're putting fish in there. I thoroughly recommend Arum Lilies for spectacular display.
Plant things in the proper aquatic baskets, get the biggest ones you can put in there. Things like Irises and Lilies will need splitting after a couple of years.
 
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Things like Irises and Lilies will need splitting after a couple of years.
My iris grows like a monster! It took two of us to remove it from the pond last year and it was taller than my missus. I just can't get anything else to grow without the fish decimating it though.
 
Tap water only needs treating if you're putting fish in there. I thoroughly recommend Arum Lilies for spectacular display.
Plant things in the proper aquatic baskets, get the biggest ones you can put in there. Things like Irises and Lilies will need splitting after a couple of years.

Agreed - although my irises roots split the baskets!
 
I have to split my arum lily every year as it is a bit of a beast.
I have it in a floating basket, surrounded by another couple either side for stability.
Looks fantastic in the summer and get lots of white flower stems from it.
 
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