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Slimy green pond

Discussion in 'Water Features' started by Watkinslawnservice, Apr 19, 2006.

  1. Watkinslawnservice

    Watkinslawnservice LawnSite Senior Member
    Posts: 378

    I don't do this kind of work nor have I ever had my own pond so I have no idea on this. A friend of mine was asking me if I could help him figure out what to do with a pond his mother has. He told me that she says it turns green even though she has some kind of filter system in it and it does have a plastic liner of some sort. She has even tried pool chemicals in it I guess. It sounds like it is a small pond, maybe like 6'x6' or so but I have never seen it personaly. Do you guys have any tips for keeping a pond clean? Thanks.
  2. sheshovel

    sheshovel LawnSite Fanatic
    Posts: 5,112

    Maybe she is not curculating the water in it and not cleaning her filter out as she should.Pool chemicals should NOT be used in ponds..they have pond alge bloom chemicals and "balls" you can throw in there.
    I would start by draining the pond..cleaning it out..cleaning out the filter and starting over with clean water..All ponds get a little green..but it should be properly cared for to keep from getting slimy green..sounds stagnant
  3. Critical Care

    Critical Care LawnSite Bronze Member
    Posts: 1,654

    This sounds like suspended algae. A chemical called Cutrine could be tried, if it hasn't already. And UV light filters will also help reduce suspended algae. Another idea is to use a flocculent, which helps to clump suspended algae together where it will then drop to the bottom of the pond or else get trapped in the skimmer box.

    Algae can easily develop in slow or non-moving water, especially in sunlight and warmer temperatures. And… there are different types of filters. Your friends mom may only have a skimmer box and filter, but possibly no biofilter.

    So, there are different options to take… or handle all options for a better chance of success.

    Actually, Sheshovel, my pond has never been green, but has always be very clear and clean... even with koi, catfish, and crappie in it.
  4. LawnScenes

    LawnScenes LawnSite Member
    Posts: 177

    When you say "turns green" do you mean the water or the bottom and walls of the pond? If you're talking about the water then you've got free floating algae that's causing your problem. This could be due to poor water movement, high bio load (lots of fish), high nutrient (wanted and unwanted) content of the water, poor filter/pump (maybe they aren't large enough for the pond), to name a few. I've found the best way to cure "green water" in ponds is with a UV Sterilizer. You can buy them in "in-line" versions or some are built into filters. Couple it to a larger filter and higher capacity pump and the green water will vanish.

    Here's the filter I use personally, recommend, and install. Very easy to clean, very easy to hide, and most importantly it works very well on small to medium sized ponds coupled with the right pump.

  5. pondfishr

    pondfishr LawnSite Member
    Posts: 115

    If it is only 6'X6' "without fish" I would clean it thoroughly add fresh water and make sure that my filtration system was working properly. If you have fish special care must be done to prevent stressing them out during the water change.

    Stagnant water with too much sunlight can cause algea. Does the pond sit in the direct sunlight? If so think about landscaping around it with plants that can offer shade during the day. This might help long term.

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