Koi Pond Liner damage caused by ...... ?

If anyone can help with this, that would be great. Copy of email to the Natural History Museum, sent today.

Quote -

"Dear Sirs,

I spoke with ****************, this morning about damage to my pond liner, which may be caused by some type of invertebrate, scratching the surface of the rubber, which the opens up due to the weight of water and is causing excessive leaking. The liner has effectively become porous, with leaking when it is full of about two cubic metres per day. Also a few years ago, when the pond started to leak, some ornamental grasses growing nearby, must have detected the damp conditions and sent down roots which sent shoots, growing up through the rubber, under the water surface, presumably through the cuts or scratches in the surface. All the grasses were removed at that time including the roots, but the problem has only got worse. I had a visit from a pond contractor, who had seen the scratches on the algae, but had never seen these scratches, becoming cuts and then in turn becoming holes in the butyl rubber. I need to find the cause of the problem, since the new liner will need to be kept free of this damage if possible. It strikes me that this issue could affect reservoirs, constructed with this butyl rubber.

 

I have not seen any invertebrates other than soft bodied ones, like blood worms, no water snails, which I have in my small pond. I do have dragonfly larvae. Most things in the pond are eaten by the carp, except frogs and toads, but they usually steer clear of the fish. Also no mechanical cleaning equipment is used, since the system has a bottom and side drain and it is a gravity system, of filtration.

 

What I would like is an identification of the cause of the problem. I am assuming it is some type of invertebrate, scratching for food, or to lay eggs. Maybe in a natural setting, the scratches would be on stone or wood under the water surface. Any help you can provide, will be gratefully received. I attach four photos of the scratches, cuts and holes. I hope that the size of the image files, does not present a problem, with the email."

Some  pictures of the problem.

Any help would be appreciated.

ChloeB & Tiger's Osprey Data Site

Sat track schedule Spring 2014

LG 7 days; RW & SWT nil; LDOP varies

  • Someone suggested it was the fish doing it, they do suck the sides of the pond, but these marks are too small. the fish are large, from 30cm to 85cm.

    ChloeB & Tiger's Osprey Data Site

    Sat track schedule Spring 2014

    LG 7 days; RW & SWT nil; LDOP varies

  • In reply to jsb:

    Someone else has had a pond liner problem a while back.

    "Can anyone help?
    I have 50 plus matchstick head sized holes in my pond liner. The liner has been in place for about 8 years and they have only appeared this year. I am eager to find out what is causing this as the water level has dropped dramatically."

    http://www.bbc.co.uk/blogs/springwatch/2009/06/a_pond_looks_great_in.html

    I`ll put my mind to it,it makes a change from the usual heron attack.Pond liner merchants do well around these parts!

  • In reply to edgebander:

    Looks like a fault in the liner to me, have you let the pond dry out at any time or it could be just an age problem

     Ray

          

             a good laugh is better than a tonic

  • In reply to Barnsley lad:

    That's what I was thinking Ray. They look like tiny splits or cracks in the surface to me rather than scratches.

    ChloeB & Tiger's Osprey Data

  • In reply to edgebander:

    edgebander said:

    Someone else has had a pond liner problem a while back.

    "Can anyone help?
    I have 50 plus matchstick head sized holes in my pond liner. The liner has been in place for about 8 years and they have only appeared this year. I am eager to find out what is causing this as the water level has dropped dramatically."

    http://www.bbc.co.uk/blogs/springwatch/2009/06/a_pond_looks_great_in.html

    I`ll put my mind to it,it makes a change from the usual heron attack.Pond liner merchants do well around these parts!

    This description is similar, to mine in one respect. Where the damage had resulted in the grass coming through in the past, that I referred to, the result is shown in the photo where I put a cocktail stick to shown the hole. I know for a fact that that hole was caused or enlarged by a shoot growing up through it, The liner has never been dried out, the level was controlled by a timer whereby the water topped up the pond every six hours, at considerable expense, as I am on a water meter. The butyl rubber is the best quality butyl rubber from Exxon/Mobil Chemicals rolled in Sweden and imported back here.(The same rubber is used to make car tyres). The guy who inspected it is a professional, not, as many are, 'gifted' amateurs, with no qualifications. The pond is two metres deep and the same small scratches/cuts are evenly distributed right down the waterline, which is very low. The level has only been dropped in the last three weeks, in order to establish the source of the leaks, but the level is still dropping, albeit at a much reduced rate.

    The cost of the solution is considerable, as you can imagine, the new liner will be £800 to £1000 and that is just the start, when the new filtration system is added, plus all the new equipment to go with it, I need to get it right. The existing gravity system will be replaced by a pump fed filtration system, with a set of pods to replace the existing filtration, which is underground. The reason for that is to replace like with like would entail too much builder work, breaking up all the concrete and paving round the edge. This a 25,000 litre pond, with 40 fish in it.

    I appreciate your comments, many thanks.

    (In a gravity system, the pump is in the filter, so the water flows into the filter via bottom and side drains, which keeps the pond much cleaner.)

    ChloeB & Tiger's Osprey Data Site

    Sat track schedule Spring 2014

    LG 7 days; RW & SWT nil; LDOP varies

  • In reply to jsb:

    I didnt know it but I have the same problem.Luckily its only my front bike tyre so not many litres there!Went down the snail trail first which led to`snail trails`in the eva component of solar panels which led to polymer degradation in rubbers then to me worrying about me tyres.

    This could be a problem for reservoirs but when have the utilities ever worried about water waste?

    It raises the question-Was the pond liner that you purchased fit for purpose?My front tyre is 7 1/2 years old btw.

  • In reply to edgebander:

    Here are a couple of shots which show that the scratches/cuts are a) below the water line and b) not only on the rubber, on the metal surround of the drain as well. The portion of rubber out of the water is not affected, just a bit dirty and aged by the sun, also the folds in the rubber under the water are clear of algae and the rubber is smooth, no damage at all.

    ChloeB & Tiger's Osprey Data Site

    Sat track schedule Spring 2014

    LG 7 days; RW & SWT nil; LDOP varies

  • In reply to doggie:

    That is really intriguing isn't it? The marks being on the metal parts too puts a different slant on it altogether. I do hope you find out what is causing it JSB.

    ChloeB & Tiger's Osprey Data

  • In reply to doggie:

    doggie said:

    Hi jsb

    Have you thought of contacting a firm that does garden ponds to see if they know what can cause it?. you could try these http://www.water-garden.co.uk/

    Click the contact us tab and you should see an email address.

    Doggie: Thanks for the info. The contractor for the job, who has not seen this type of damage before is this one. He is working out a solution, but everything will have to be replaced, including the filtration system, as I described earlier. I am an experienced fishkeeper and ponds can be a nightmare, most of them leak, sooner or later. Concrete ones like swimming pools, when they leak.....well one day you go into the garden and the ground opens up and you fall into a huge hole, that has been created by the leak over the years, without the owner ever knowing. The leaks are sometimes masked by the need to do regular water changes.

    My concern is the after the job is done, what is to stop it happening again, if we do not find out the cause.

    ChloeB & Tiger's Osprey Data Site

    Sat track schedule Spring 2014

    LG 7 days; RW & SWT nil; LDOP varies

  • In reply to doggie:

    A heron was standing over the pond this morning, but unable to catch anything as the water surface was well out of reach. Nevertheless, I shall put the covers back today. Fish could be caught if the bird, went into the water, as in parts it is quite shallow.

    ChloeB & Tiger's Osprey Data Site

    Sat track schedule Spring 2014

    LG 7 days; RW & SWT nil; LDOP varies