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Pond water

We have a fairly new pond - filled with well water which has been filtered through the ground, so basically rain water.

Some of the new oxygenating plants were eaten by a pair of ducks, the other oxygenators have died.  The marginal and lily plants are alive but don't look too healthy.

The water in the pond is clear - there are plenty of water boatmen and there were mosquitoes which thankfully have now flown away.

Why are the plants struggling to survive?  We are having the water tested tomorrow at a shop that deals with ponds and plants.  Could the water be too acidic?



  • Thanks for your reassuring words Phillippa. We will know more tomorrow regarding the state of the water PH but it is quite alarming to see a whole lot of new plants dying in front of our eyes over a matter of 3 or 4 weeks.  This is the time of year when they should be establishing and spreading.

    The plants around the perimeter of the pond and bog garden are all spreading and some are now flowering, which makes the pond look stark by contrast.

    We won't give up but we just want to either put things right or be told that the levels are good.

    We didn't add any water from an established pond - and we didn't use any tap water either.

    By the way, the dianthus seeds that you sent me are almost at the flowering stage.  They look very dainty, but were very easy to germinate.

  • As an up-date, our water has been analyzed, the PH is 9 and the nitrites are high too.  We have been advised to remove one third of the water and top up with tap water instead of well water.  We will then analyze the water again and hope it is as it should be.  

    We have been told we will have to test the water every month!  With 17,000 litres of water, I hope we don't have to go through this water change every month too!

  • FairygirlFairygirl Posts: 52,097

    Oh GD - I'm so sorry you're having a problem after all your hard work and effort. I hope it can be resolved relatively easily. I'm sure once you've replaced some water, things will settle, as Philippa says.

    A good few weeks of rain might be very welcome - even if not for you!

    Have you taken the plants out and relocated them in a temporary home for the time being? It would be worth doing if you can - to try and save them. Buckets or anything you can find.  They're expensive if you have to start replacing those image

    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • Pete.8Pete.8 Posts: 10,284

    Hi GD2 Have been keeping an eye on your thread with interest. My little pond is coming along nicely too I'm relieved to say. But I've had the same problem as you. Most of the oxygenators I've been putting in since March have just withered and died. Marginals are doing ok.
    I put some elodea (sp.?) in 10 days ago and that is now growing. I also noticed that bits have survived from other plants I dropped in a while back, so I'm hoping they'll all start getting underway now. The water was pea-soup for 7-8weeks but now crystal clear with a brown tint and home to at least 6 newts and numerous other things in and on the water.
    I've kept tropical and coldwater fish for ~50yrs and tbh it would be unusual for a new pond or fish tank not to get a nitrite spike as it settles down, usually caused by decaying matter - filters usually help keep this down. I've just checked the pH of my w/l pond and it's 8.6, so not far off yours. Lots of plants would normally keep a w/l pond in balance, but often goes out of kilter late autumn if a lot of dead plant debris builds-up at the bottom and if not cleared can cause a huge nitrite spike the following spring - much less so with a pond your size though.
    If your plants are growing ok and you can see growth gathering pace (as I can with mine) then you may be best leaving it for the plants to deal with. But, the only downside to replacing 6,000l is you may get an algae bloom for a few weeks but on the plus side, your garden gets a good water.

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • Pete, thanks so much for your input - and I appreciate the thoughts from you all - it is swings and roundabouts and obviously it is disappointing to see new plants wither and die, especially when we don't really know too much about the water content - at least with garden plants you can usually work out the problem or move the plant to a more suitable place.

    We are now just refilling with the tap water, and will hope that this water change will solve the problem.  Luckily we have another smaller pond (artifical preformed shape), where we have never had a problem with plants dying and we have plenty of oxygenating curly worley weed in it (what is that called?) which we will transfer into the larger pond and see if that survives and grows.

    I have just read that putting household vinegar in the pond water may help - I must look into that because topping up from the garden tap (mains water) every month will be costly and far more effort than throwing in a cup of vinegar.

    At the moment there are no shady places for the newts and other pond creatures to hide in, although there is some silt in the bottom of the pond, it has full sun on it for most of the day.  I have taken note of your comments about the decaying plants and nitrite levels Pete and try to remember all these facts. 

    In the meantime, we are still enjoying seeing the blue tailed damsel flies and dragonflies too.

  • FairygirlFairygirl Posts: 52,097

    That elodea stuff is tough as anything GD - it'll survive pretty much anything, so once that establishes, it'll help. I expect your well water will be quite different from standard tapwater, but I'm sure things will settle down over time. Saving the plants in the pond is probably important at the moment though.  

    Have you got any biggish plants in pots that you can stick nearby to give a bit of shade to the surface of the pond - at least for a few hours? You could try the watercress chcuked in to see if it soaks up a bit of the excess nutrients too.

    We don't have to worry about too much sun here just now - it's been very sparse in the last two weeks - a few hours here and there. Grey and damp again today. Standard Scottish summer weather  image

    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • a1154a1154 Posts: 1,058

    Hi GD sorry if you are losing plants, but you are rushing something that takes time to balance. I wouldn't change water, or put vinegar in (is there any evidence for this?) and definitely don't take water from established ponds, this doesn't help anything but does spread disease. There is nothing wrong, it's just new. 

  • No shade Fairygirl - the pond is very big (by comparison to most garden ponds.

    We did put in two small bails of barley straw once we had added the tap water this afternoon, but clarity of water isn't the problem anyway.image

  • Pete.8Pete.8 Posts: 10,284

    Would very much agree with a1154 GD, don't go putting vinegar into your pond.
    Are you sure the rocks aren't contributing to the high(ish) pH reading? A pH of 9 is on the high side but not really excessive.
    You can do a vinegar test on the rocks - not overly scientific but will give an indication. If a few drops of vinegar causes fizzing on the rock it's not suitable.
    A little shade for part of the pond would be nice, a small evergreen of some sort possibly.

    You can't rush nature, it WILL all settle and look even more beautiful as it all matures.
    Quick fixes can sometimes cause long-term problems.

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • Pete.8Pete.8 Posts: 10,284

    P.S. fg's suggestion of watercress is a very good idea. It will use lots of unwanted nutrients etc.
    If you get some good watercress with long stems from the shops. Using a small planting basket (or 2), put the watercress in then fill with gravel and bury it in the long run of your waterfall so the basket is just below the surface and the watercress floating on the water stream. Mine is growing strongly in the fish pond waterfall this time of year. I do eat the stuff that grows above the water it's almost as hot as a chili!

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
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