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No silt or a little silt?

I'm in the process of emptying our pond and sinking it deeper into the ground as it was put in a bit wonky! It has become entirely solid with flag irises and marsh marigolds such that there was no clear water - earth worms were even living in there! I've taken out 2/3 of these plants but left a lump as the frogs adore them and the various critters feed off the decaying leaves.

Disrupting the wildlife is concerning me however, and I'm not sure how much of the silt to remove. There's maybe an inch or thereabouts of silt all over, and it stinks when dredged up, but I understand frogs sometimes hibernate in it and the leeches, flatworms, waterlice and maybe the snails too all use it for various purposes.

Would it be best to remove it all and accept that it will inevitably gradually build up again? Or should I save some to put back in there when I'm finished to disrupt the balance as little as possible? I am saving the clearer water and have plenty of rain water to top it up (the waterbutts even have little pond snails in! It rains snails round here it seems!)


  • nutcutletnutcutlet Posts: 27,412

    Not everyone wants the same thing from a pond any more than they want the same thing from a garden.

    Some want the sterile version, clear water, no soil, plants in baskets, fountain and fish. Others prefer the wildlife friendly version. There's no right or wrong. 


    In the sticks near Peterborough
  • PanoplyPanoply Posts: 75

    Yes, thank you nutcutlet. I think I shall add a little of it back in and let a few leaves join the mix so the frogs still have some protection and the little critters something to eat.

    I've also seen a lot of the websites you mention Sara, that make out that any amount of silt will be the death of the pond, with people saying how they clean their pond out every week or every few days. Seems quite bonkers. Ours hasn't been touched in years and it is full of life, so it can't be so bad!

  • nutcutletnutcutlet Posts: 27,412

    Sara, baskets also  stop invasive plants taking over the world to some extent. You can lift them out basket and all if you're strong enough.


    it can be difficut to get plants established in a plastic pond if there's little or no soil at the bottom


    In the sticks near Peterborough
  • Forester2Forester2 Posts: 1,477

    Yes, leave the silt.  As I posted on another thread (So Exciting) I have a tiny pond and was clearing silt from the bottom, as I thought it was building up too much, and I found four frogs hibernating at the bottom, so I put it all back.  The water is always clear as well, so it must be OK.  I have also posted a photo of one of the frogs on that thread.    

  • Mrs GMrs G Posts: 336

    I have a tiny preformed nature pond and I have to use planting baskets or the crows and magpies knock all the plants to the wrong depths. image

  • you need some silt in the pond because dragon flies live in that and also various other things-.

  • Dave MorganDave Morgan Posts: 3,123

    Biologically speaking, every wildlife pond must have silt. The microbes and insects which rely on the pond need this silt to break down detritus which gets into a pond. It supports a whole range of pond life which rely on the reactions within the pond. And by the way, the really smelly stuff is the best starter you can get in any pond.

  • PanoplyPanoply Posts: 75

    Thank you all for your replies. It's brilliant to hear the silt is a good thing and I shall keep it by to put back into the pond. I'd read about people using it on their gardens and hanging baskets and how it was wonderful for the plants, so it makes sense it'd be wonderful for the pond too! I've not noticed any dragon fly nymphs before but I'm hoping clearing the solid mass of flag irises out will enable them to make use of our pond next year. 

    Now if only it'd stop raining for a day so I can get out there and get it done. Hoping to get it out, dug and back in again before nightfall to cause minimal disturbance, but that might be wishful thinking!

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