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Mini pond not healthy

I started a mini pond in Belfast sink last year... It has some pond plants below the surface but has been green since mid Summer. I was hoping it would clear itself but do I need to do something else... If so what.
Hhopefully pic attached


  • FairygirlFairygirl Posts: 54,350
    Harder to keep small ponds clear. The water warms up much more easily, and it's a better medium for algae, blanketweed etc to grow in. If it's in the shade, it won't help it either, as a small volume of water can get stagnant and sour quite quickly.

    If you don't want to use some of the proprietary products for clearing it, you can try chucking in some watercress - just the stuff you can buy from a supermarket, and no need to put it in a pot or anything like that. It uses up some of the nutrients that the algae like to feed on.  :)
    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • iceice Posts: 332
    Watercress caused the green was ok till I tried that. Thinking of trying barley straw... Once I've found old tights
  • Pete.8Pete.8 Posts: 11,126
    The plants you have put in your pond are not awake yet.
    The algae which causes the green water is, so it's making the most of the nutrients that have built up.
    Once your plants start growing in about a month, they start using the nutrients and the algae will starve - that's the theory anyway. It may get worse before it gets better.
    I agree with @Fairygirl re. the inherent problems with such a small pond, but try leaving it until your plants spring into life - in spring :)

    If there's build-up of silt at the bottom, it would help to remove some of that, as that is what is providing food for the algae.

    I use Blagdon sludge-buster and in a pond the size of yours you'd only need a tiny pinch every 2 weeks - it may help.

    Billericay - Essex

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • FairygirlFairygirl Posts: 54,350
    Hmm - I doubt watercress would do that. It would just grow if the water was suitable. It's algaes that are causing the green colouring, or else there's a lot of decaying debris in there. That also happens more readily in a small volume of water  :)
    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • Agree with @Fairygirl The watercress is unlikely to have caused the green water.  It's usually too busy growing and covering the surface.
    A Belfast sink doesn't hold a large volume of water and so you are always going to be battling against that. You don't mention the aspect/site but that will make a difference too.
    If you only started the pond last year, it hasn't really had time to "settle" and neither have your pond plants.  You don't say when last year you started the pond or what plants you used but your pic would suggest it was later in the year rather than earlier.
    Before you give up, I think @Pete.8 is quite right in suggesting that you give it time to get going and see what it is like come early summer.
    Here's hoping that it will prove to be successful :)
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