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gknee_50

Can't clear up pond water, have tried everything!

gknee_50
15 years ago

I hope someone has some advice for me. We put in a pond last July. It is approx. 2000 gallons. We have a skimmer and a waterfall with a good pump. We put rock in it to cover the liner and added dry bacteria, de-clorinator and barley extract. My water was clear in March, but since the water has warmed and I began feeding the fish again...it is brown. I put in hornwort, put in my hyancinths, and have cut down on feeding the fish to twice a week. Should I drain my water and start all over? It has been brown for 3 weeks now. We put an aerator stone in it also to help with oxygen. I was thinking of taking out 20% of my water every week for about a month....do you think that would help the problem?? I would appreciate any advice! Thanks!

Jeanne

Comments (151)

  • Calamity_J
    10 years ago

    I have a uv bulb(9watt) in my pressure filter setup, and it keeps everything clear! I had an otter get in a while ago and the pond was a cloudy mess, but two days later everything was crystal clear again!

  • delaney276
    10 years ago

    Listen to "Horton".........
    also...I filter with floater plants...water lettuce...hyacinth....hope everyone enjoys ponding in 2013! Dave in WV......

  • NCgardenmouse
    10 years ago

    I have been following this link for a bit now & have found many a good idea. Last year I built a small (+-300g) pond, outfitted it with plants, goldfish, & a 330 pump/filter kit which did very well- for a time. My waterfall is pathetic, I am constantly clearing the spray head & now am experiencing the "tannin/green water experience". I am in the process of 1) increasing pump size (tried 700gph-still wasn't enough: 2)adding UV (should it be through pump or filter?) & adding external filter. I agree w/the poster that said to go above what is estimated for pond size, but am still at a loss for just what gph to shoot for. And should the uv be on the pump or the filter? Any help would be most appreciated- I have had successful ponds before but this is my first in North Carolina & my first post to this forum; not sure if I am in the right place or??

  • jacob12345
    10 years ago

    Try a product called SeClear. I know people are not as fond of chemicals on here, but it is a great product. It kills some of the algae with its algaecide product, but it also clears up the water. It helps lower phosphorus levels and helps clear up the water.

  • greygoose9631
    10 years ago

    My pond is less than a year old and I, too, have green water. I tried the poly batting in the can to filter the green floating algae from my pond and was not successful. Either my batting wasn't dense enough? Or my algae is to fine? I held a glass to collect the filtered water and dipped one in the pond and both were the same green.

    Following the failed algae filter I ended up draining about 60% of my water. I did find my young koi hiding below. I hadn't seen them in days and wondered if they were even still present. I refilled and declorinated and the water is better but still a green cloudy color. I have removed some of the rocks and plan on removing more, which is frustrating because a majority of my time was spent placing the rocks in the pond. :) But alas, I will prevail and have clear water!

    I'm going to try patience for a few weeks and see if it clears. I wouldn't be nearly concerned except I only placed my koi in the pond about a week before the water clouded and I'm curious to watch them and make sure they are healthy!

  • Catvision
    10 years ago

    Lots of good ideas here, thanks. Yeah, I had green water, brown water and lots of string algae last year. I'm in Northern Colorado, zone 5.
    I have an 1100 gal pond, 30" deep with a simple pondmaster 2000 mechanical filter that sits on the bottom. We have 12-15 fish (1 koi and goldfish and 1 hifin shark who is an algae eater.) I also add Aqua One or similar beneficial bacteria all year round - the regular formula during the summer and the cold water kind from Sept until April or May.
    This year I got on top of the string algae early - in March as the sunlight is increasing. I learned the hard way that if I don't do that and stay on top of controlling it early then it's a constant battle to try to clear it.

    Several things are keeping my water very clear this year - we can see down to the bottom. 1) Keeping a .3 % salt (pond salt) level in the pond. For my size pond I added about 30 lbs of salt in a new water pond (since we drained & cleaned it completely last year). I bought a mesh bag and added about 5 lbs of pond salt every few days and left it in the waterfall to gradually increase the salinity level. This does a great job of keeping the string algae under control. My pond store will do a free salinity water test so I brought in a water sample every week until the level was point 3 %. It is good for the fish and the koi, goldfish and a Chinese hifin shark are all active, healthy and look great.
    2) The water was cloudy until I added the activated charcoal filter pad to my filter. What a difference! The water cleared in 3 days. Now it looks great.
    3) Netting out the gunk at the bottom every few days to reduce the load on the filter.
    4) We bought inexpensive bird netting and cover the pond when the leaves start to fall. This helps a lot with reducing tannins. Some leaves still get in and I net them out.

    Yes, patience is really important since all ponds must become eco-balanced and you can't rush the process. Since we drained and cleaned it completely last summer it didn't completely balance before the cold weather but is working nicely now, looks balanced and is doing great.

  • Arbust69
    10 years ago

    Finally clear water! After trying several things on these posts I have crystal clear water. My pond is about 1000 gal. and 34inches at its deepest with 2 shallows, 4 lilies, 6 water hyacyths, 7 red minnows, and 7 small comets. New water 2 months ago after we moved in (10 inches of sludge and dead fish in the bottom)
    Things that worked;
    rocks are only on the shallow shelf area, where they can be brushed weekly,
    adding benifical bacteria at 2X the recommended rate for 3 weeks,
    homemade filter (made from a milk crate , lava rock, cut up chair cushion foam, and quilt batting, made a sack to encase the pump with filter stuff, wrapped it in quilt batting and closed it up with zip ties, too about 30 min.) I pull the filter out of the pond once a week and hose it off and dump it back in.
    I brush off the rocks once a week with an old corn broom and skim out debries 2X week.
    I can now see all the way to the bottom, even a 1" pebble.
    It took about 8 day for the water to fully clear after putting in the filter rig.
    I'm in the desert and get lots of sun plus pinon needles falling in.
    The best advise I got was calmness and wait.

  • Brenda65
    10 years ago

    I started using the batting this morning but my pond water is coming through green. It is a clear green with no string algia. Just cannot see through it in the pond. We have added a biological filter and aireator and a dose of Tetra Pond Algia Control. But nothing clears it yet. We added the homemade biofilter about a month ago, The areator this week along with the Tetra Care. It hold about 500-1000 gallons. Has at least 30 gold fish and one Koi which all appear to be very healthy. It is lined with rubber roofing. Any suggestions. I know patience but the only improvement I have seen is some slight clarity of the green color. Also put netting over the top to keep leaves and the cats out. Dipped alot of leaves out of the bottom before running the temporary batting filter. Help!!!

  • PondNOOB
    10 years ago

    I have had a pond now for 3 years and have been constantly fighting the water clarity issue. Being above the 49th parallel, we have brief (5 month) summers, which sees very long daylight hours (gets dark around midnight on the solstice) so algae blooms are hard to battle. I have tried introducing as many plants as possible to get as much shade as possible on the pond, as well as beneficial bacteria, and using a ionizer which introduces copper into the water to fight the algae. I will also try a few of the suggestions posted here, like extra filtration, activated charcoal etc, but just wondering if there are any other Canuck ponders, that have fought these battles and won ?

  • tuder96
    10 years ago

    Hi everyone, I am the webmaster for the Koi Club of San Diego and as such I am always looking for new material for the site. We have a pretty informative site, with links and articles from some of the top in the field. If you would like to submit an article or story, pictures or what ever please contact me at info@koiclubofsandiego.org
    good stuff on algae by Norm Meck water quality expert.

    Here is a link that might be useful: ponds

  • mckool
    10 years ago

    Shalom, plants are great for filtration. I only use batting and gravel to hold in the batting and for plant support, fertilize with either job tomato spikes or miracle grow plant spikes. Has worked well for about 8 years, maybe longer I can't remember when I first started doing this.

  • topsiebeezelbub
    10 years ago

    My water turned brown overnight when a few pecan leaves blew into the pond...tanin. I cannot imagine changing the water every few days to keep it from turning tea color...its a pond not a swimming pool...as long as its not algae don't worry.

  • fairiegarden123
    9 years ago

    Hi. I am new to this site but I would like to share my experience with my pond I have had over fifteen years. I have numerous goldfish and one koi. I don't have an algae problem because my pond is primarily shaded. I have a rubber lining and recently removed the rock from the bottom of the pond because like many of you experienced, it traps a lot of gunk. After removing the rocks my pond got muddy. My biological filter system is a lot like many of you have had success in. It is an above ground plastic tall 3 ft bucket. It is filled with lava rock and on top every spring I throw watercress on top and it take root into the lava rock. I never ever have had a algae problem and monthly testing always indicates water quality is safe. All my fish are happy and healthy, I owe it all to my filter system. Now that I disturbed the bed which held a lot of gunk from leaves, I have took some of the lava rock out of my filter and added batting as many of you have said helped, in hoping to speed up the clearing up process. I am also going to take the advice of using a milk crate in the bottom of the pond, use my left over lava rock, add more bating and lay my pump it. This should help speed thing up to my pond clearing up sooner. I only did one water change in all the years we had this pond and my water was cloudy and the quality was not good. I won't even think of doing a water change unless my tests tell me my water is not safe for my fish. I also added beneficial bacteria after removing my rock just to be on the safe side and to also help speed up the breakdown of the particles. So in a nutshell, the lava rock biological filter system has been successful in the long run and I look forward to many more years of pond enjoyment.

  • johnny bravo
    8 years ago

    I've had clear water in some ponds and uncontrollable murky water in one pond. I don't have scientific information but I want to log what works and what doesn't work. this is mostly notes for my future self.


    I think the answer to clear water is a proper balance. Unfortunately it's hard to measure exactly what is in balance and the balance needs to mostly be reached on it's own because you can't control many factors like the type of water you have, nor what the rain is like or what comes off surrounding trees (think pollen, not leaves). Here are bad ideas, followed by suggestions:


    - use a small filter. on the clear ponds, the filters contained about about 5% of the pond's volume, meaning they were huge. they could hold lots of sediment and suspended particles before clogging. Right now my pond is 3000 gallons with a 200 gallon filter

    - have low water flow per hour: 1/4 of the pond's volume circulating per hour or less is bad. 3/4 to 1 times the volume per hour works well. A quality pump can do 2000+gph around 140watts. It is important that this water flow does not stir up the bottom of the pond, which is hard with this much flow. an idea is to add a wide waterfall (4' wide) that flows, but doesn't roar.

    - don't add air: adding a large waterfall or air stone helps keep water clear by adding air to the water. everything in your pond needs air, from fish to insects to amphibians to bacteria.

    - don't add bacteria: i have an established filter from someone's old (clear) pond full of bacteria. i also regularly add water from my perfectly clear indoor aquarium to the pond, perhaps 5-10 gallons once a month. The idea is bacteria in this water is established and correct so it can setup and help the pond. once setup, you don't need to add new sources. your pond will eventually find this on it's own but adding it will help, especially in spring when the bacteria count is low.

    - don't add fresh water. even my clear aquarium which is heavily planted needs new water once or twice a month. evaporation is one item but new water is needed, and old removed. the good news is the old water is excellent for watering garden plants with and new water is already clear (with a bit of chlorine to hopefully only kill bad things). 5% water change a month is my target.

    - don't clear your filter. depending on the amount of suspended particulate in your water, the filter may need to be cleaned once a week or once a month during summer. it's gross, but do it. also the brown water that comes off the filter pads is excellent for watering plants... save this dirty water in buckets and water your plants throughout the week!

    - don't add a UV filter. the best thing this does is causes suspended particles to clump together, allowing a filter to capture them. it can damage some cells but not by too much. i've never had a clear pond without one, however this one is debatable.

    - change everything all the time: a balanced ecosystem needs time. add the above elements once a week and note the changes. maybe something that works well for me doesn't for you and this way you can isolate it.

    - add tons of underwater plants: guess what they do in winter? die or go dormant along the bottom, making a thick layer of nutrient rich muck for spring. limit it to water lilies and anything that starts growing on it's own. duckweed is also good, the fish eat it and it's easy to remove, it also removes nutrients from the water while likely adding bacteria that was stuck to it and outcompeting other plants (cyanobacteria) for light. some underwater plants are probably good, they have the right bacteria and some have allelochemicals which have a limited and debatable impact on how they can prevent green water. i keep a small amount of elodea (currently elodea hydrilla) in my ponds.

    - remove all algae: you need this. it may not look ideal, but it looks natural, providing there's not too much. hair algae is not the best thing to wish for, however any pond i've seen with hair algae doesn't have other kinds of algae. i think there's something it does in the water to cause this. if it gets too long, remove it.

    - make a shallow pond: i have never been able to keep a pond less than 3' deep clear. 2' and less is a nightmare. i've never seen someone else with a clear shallow pond. 3.5-4' seems to be the sweet spot between digging, and low maintenance. the deeper the better, it's just harder to maintain if you need scuba gear, or need to call a water truck to fill it :)

    - don't put things in your pond. a liner bottom is the easiest to maintain, the liner still has lots of surface for bactera. don't put wood in the pond or anything else that breaks down. large rocks that give fish hiding places is ok.

    Alright, there's a recipe for clear ponds. Maybe I got the important topics, maybe I missed the most important things. Either way, this should help a bit rather than harm.

  • fairiegarden123
    8 years ago

    My pond is now crystal clear since I removed the rock on the bottom. Monthly I throw in a sludge remover pellet which keeps it crystal clear. My pond of fifteen years has never looked better, fish are happy and healthy. Lava rock biological filter and an adequate pump make it all possible.

  • mckool
    8 years ago

    Great; I don't think you can have too much filtration - rule number 1 is nothing tends to happen quickly in a pond. Bentenite(sp) will also help clear green water; think tablespoon per 100 gallons, but it is hard to mix, I use a kitchen hand blender to mix with about a quart of water, pour some into the pond, then dilute the remaining mix, I do it several times until the quart container is empty.

  • lakecitybrass
    8 years ago

    I have had a 2000 gallon pond (approximate) since 2002 and generally the pond water has been fairly clear. I am not looking to create pristine water. After all, it is a pond. But, I have had periods when the water was green for weeks or more. The water always tested ok, though.

    Then last September I added a smaller, raised pond that fed into the older pond - with the Skippy filter feeding the new pond - and the water turned clear very quickly.

  • Aseel Aseel
    8 years ago

    My pond is 8 feet deep 10/12 width feet I have about 16 large medium and small koi & butterfly koi... It has plants like water lilies and horse stick thingys the water is always green muddy would it be from the soil in the plants because there is soil under a rocks and that paper thingy that doesn't let the rocks mix with soil but anyhow I need my water clear for a birthday party in 8 weeks

    Please someone help (water clarifier) any help

  • meyerk9
    8 years ago

    There is special potting mix for aquatic plants. It's not soil at all but a media of gravel-ish pebbles. I started using it last year with great results.

    http://www.apifishcare.com/product.php?id=705#.VUtLJsu9KK


    You might need to clean your filter (with pond water, not tap water) several times a week plus water changes to get things under control. Feed sparingly, too. Also check your hoses. Those can be really dirty.

  • johnny bravo
    8 years ago

    meyerk9's comment on cleaning the filter with pond water: i need to add this to my list of success items. in summer, elevated levels of chlorine can kill beneficial bacteria living on the filter media. pond water is best to clean the filter, I just grab a couple buckets and use that, then water my garden with that opaque mud-brown water that's left.


    for potting media: you can buy the more expensive pre-made items in stores. these have a gravel consistency and won't cloud the water... but are really expensive. an alternative that i use is as follows:

    one bag of black earth from any garden center. make sure it only contains black earth, it cannot contain those little white fertilizer bits. those bits are lighter than water, will float out of your mix, into your water providing a permanent source for green water. with straight black earth, compact it into a pot, plant water lillies, etc and then add pea gravel on top, a about an inch or 2-3 cm should do it. if the soil is compacted, by the time the koi remove the rocks nothing will happen.

  • Cindy Mcdaniel
    8 years ago

    I have used a rectangular plastic as a basic form for a filter basket. Then rubber shelf liner, aquarium carbon filter cartridges, fine nylon bath sponges and small bags of gravel in knee highs or screen bags. Pack this around the pump to protect, wrap with shelf liner to hold the stuff in place, making slit or small hole for out flow tubing. And use the plastic tie straps or plastic bungee straps (no metal) to slip around the basket. This can stay in pool 1-2 weeks Scoop it out with fine net to catch the dirty water. This works quite well for small pools. ...... I have found putting small gravel in the basins /levels from a waterfall will really clear water..... Sorry for the pic Didn't know how to delete it.

  • Lisa Puto
    8 years ago
    last modified: 8 years ago

    I have been planning and studying to build a dual water feature( 2 ponds) connected by a man made stream at our home for over 3 years and we are finally under construction as of today

    Need advice: I have read this entire blog and I have been studying natural swimming ponds and how they are filtered and built to almost as a mountain spring and they filtrate them selves.

    The pond will be constructed w two water features, one with a water fall and then a connecting stream . The first water feature will be a 15X 15 round plant water feature that is 5' deep in center with shelves for plants, w/ pond liner . The water fall will come out of a mound with a pump into the pool of plantings using a basic submersible sump pump rolling down over rocks dropping into water causing it to circulate etc . The water will then travel down a 10-12 ' stream into a Swimming pond 40' X 20' 9-10' at deepest part ; with no plants and approximately 8 koi fish and a clay bottom . On the farthest end of the swimming pond it will have a jump rock into 9-10' of water for my boys to swim . We are adding an elevated gazebo with electricity etc to sit next to clear water. The goal is to use the planting water feature to filter the water so it will be clear in the swimming koi pond .

    The gentlemen digging and helping me with extensive pond building thinks two submersible sump pumps pushing the water up over the water fall into the planting pond feature and then down the small stream with additional plantings and pebble rock etc will be enough filtration. He would like to use pond liner in the planting pond and clay in the larger swimming area. I am debating liner for both .

    I want plenty of filtration and good bacteria balance - I believe in theory if you build a pond right it can filter itself like a mountain stream or a septic system

    1. So DO NOT put gravel at the very bottom of either pond? Just add gravel on the shelving of the lined plant water feature and NO GRAVEL at the very bottom of the planting pond to prevent sludge build up . seemed to have some mixed messages on this .

    2. Is it safe to assume the water all and the stream or flowing stream between the two water features will act as a skimmer and a filter with the rocks and plants and the additional filter at the top of the water fall is not necessary??

    3. Do I understand correctly the planting pond if perennials and several plants gets to fall then it would be safe to pull the annuals out before freezing and clear it out planting pond to prepare for winter . This will prevent the break down of all the plants and sludge for coming spring ?

    4. Are Koi water stirrers and cause the pond if it has a clay bottom to be mirky muddy stirring up water? I know they will eat plants and they are bottom feeders . Need advice for them .

    5. How much water and plants gravel etc to counter act the 8 Koi in the water and debris ?

    6. For Ohio what should I prepare to add to the water as the water shed will be high for our lot and we will get quite a bit of fertilizer run off into our water

    7. I was told to use our city water to fill it and to periodically put fresh water in the ponds if low or ? I am worried to put a littel city water in it to not kill the good bacteria or balacne and if we cant what is the suggestions ? do this because the water will not be softened first .

    8. I know there are several water plants but what is the fastest and best to use for a new pond. We are doing shelving so that 6" 18" 2 ft and then floating plants will do well

    9. When planting we need to be careful of soil and what we put in the water - no fertilizer and using clay kitty litter is good if putting in a pot or etc make sure the fertilizer cannot escape into the water ?

    10. I it ok to use submersible sump pumps instead of a regular pond pump ? ?

    11. What type of UV should I use for the bodies of water ? The features both will be in full sun all day long no shade . We were told not to use UV .

    12. neither water feature is near trees . What type of bushes and or trees are best to plant near a pond so it does not drop into and change the tannins of water etc ? What is easiest and safest ?

    14. Lights I would like to add LED lights . Which are the best to purchase etc ? IS this dangerous to put colored lights in water for night time ?

    I have an olympic size pool pump i purchased last year should I incorporate it into the pond some how ? Should I sue it with a sand rock filter. The one I purchased is the kind you bring it in for the winter . Or should I purchase another different kind of pump ?

    Any advice will be great as I am right in the middle of construction and it should all be done in 5 days and I am wanting to make sure we DO this right !

    Lisa

  • PKponder TX Z7B
    8 years ago

    You should post this in a new thread. The original thread here started years ago. I would not allow children to swim in a koi pond. I may be wrong but I believe that there could be a risk of bacteria from the fish causing a minor scrape on a kids knee (for instance) to become infected.

    That is only my opinion though.


  • johnny bravo
    8 years ago

    Kids swimming in a pond are going to drink the water, inadvertently or not. Kids also have cuts and scrapes all the time. The water cannot be so dirty as to get them sick.


    If my kids get a fever after going in the water or their scrapes turn green, they can't swim in the water... though before they go in, it's usually so clear I can count the number of pea gravels on the bottom surface. If the water becomes murky or otherwise dirty, chances are they won't want to go in.

  • waterbug_guy
    8 years ago

    Aeromonas hydrophila is the bacteria Koi owners refer to in Aeromonas Alley. Present in probably every pond. It's also a bacteria made famous by news shows for being the flesh eating bacteria. Ya know, eats the arms and legs off type deal.

    There are risks. But we also have defenses.

  • Paige Draheim
    8 years ago

    You said you put "rocks in it to cover your liner"... I hope you did not put rocks on the very bottom of your liner. If you did all that fish waste will get in-between those rocks and it will become very hard to clean it out! Even treating it..... everything you treat in your pond will go directly to that fish waste first. that is why your pond has not cleared up. i would get those rocks out of there. Even if you were to vacuum it is impossible for you to get to the very bottom of the rocks where the waste is clumped together. Again everything you treat into the pond will go directly to the waste and not help clear your pond at all.


    I work at select stone in Ohio and have been trained of this knowledge by expert pond individuals whom I work with.

  • Sue Delcour
    8 years ago

    I am needing some advise on my outdoor fish pond... It is partially shaded and I have elephant ears and hostats around it, But my water is always a merky mossy green color... Any advise on what could be the problem?

  • lmjk1221
    8 years ago

    Sue, this is an older thread that you are posting on. I think you'll get more help if you start a new post.

  • warmbadverwe
    8 years ago

    I would like to share my story of a new pond and algae. My pond is about 2 months now. On the first month the pond starts to get greener by the day. I build a bio filter, it only helps to clean the water but not the algae. I read through all you posts and realize that I must try the UV light. I was skeptic about the light in the beginning but with great success it works really really well. Here are some before and after photos of my pond. Thank you for all the good posts and stories.









  • David
    8 years ago

    koilady

    I've been there too. As a matter of fact, our 10,000 gallon pond was so green that we didn't see our fish for ten years. Then, we learned about filtration and in building the system we have now, our ponds are always clear. If anyone wants a diagram of this filtering system, let me know and I will send you one. I also promise you that if you built it properly and make it large enough not so much for the size of the pond but for the amount of fish you have, you will never again have a green pond or suffer from hair algae.
    Do it the natural way with filtration. No more barley straw, u.v. lights and/or chemicals. You won't believe how well this filtering system works until you make it.

    Yours Koily, Lorraine

    -------------------------

    Koilady, per your offer, I'd like to receive a copy of the plans for your filtering system. No matter what I've tried, I also cannot keep my 1,000 gallon pond clean. Send me a private message and I'll reply with my email address. Thanx.

  • Hal Warrick
    8 years ago

    On Sept. 11th I posted This ....."I've had ponds for many years, mostly in the 12-1500 gal. range. I've
    tried to make what ever I could to help filter the water. I see all the
    comments on rock on the bottom and the fact it collects gunk and is not
    good for the fish. I have always had no rock on the bottom of the ponds
    and there was always stuff that collected down there. This last build I
    decided to do it with 1/2" size gravel all over the bottom and shelf's.
    Looked good when I filled it then added my fish, overtime the water came
    back to the green cloud we all know. So I read as much as I could find
    on pool sandfilter adaptations for the pond. Ended up with a homemade
    skimmer feeding into 4- 4"wide brushes then to a pump rated about 1200
    gph. From there it feeds to another pump ( pool cartridge filter setup
    w/ no filter ) then to the UV lamp and into a rescued pool sand filter
    filled with poly strapping. Packed as much as possible in there. Now to
    the rock filled waterfall spillway. In the second day it was going from
    the green cloud to clearing up, after a week and ahalf I can see the
    bottom ( 2.5' ) down. You know what I realized after watching the fish
    for hours, they clean the gravel bottom and move it around."

    Yesterday getting ready for fall / winter cleanup I got into the pond and roughed up the bottom gravel. In a few minutes the pond was a blackish color from the gunk in the bottom. Today after I got home from work and I can see the bottom once more. I enjoy this type of pond filter. As McDuck would say " oh what a Happy little Miser ".

  • akarinz
    8 years ago

    koilady I would like to have a copy also.

    Thanks,

    Karin

  • Sue Jimenez
    8 years ago

    I am new to the fish pond. We moved into our house in January. The fish pond is kidney shaped, and we figured out it is about 800 or 900 gallons. There are approximately 20 goldfish in it, not Koi, but most are about 3 or 4 inches long. The pond was clear after the spring thaw, but soon got pea green shortly after. I bought a good book "The Living Pond" and tried to follow all of the suggestions. We had a couple of "algae blooms" in late June and early July, but things cleared up for a few weeks. I had a "pond guy" come out to give advice, etc., which was helpful at first (he disappeared!). He hooked up the pressure filter (which the previous owners were not using, as we discovered), and advised us on barley bales, DSolv9, Clarity Max, etc. We have been trying to follow his suggestions, but since mid August, the water has remained pea soup green. He came in early September, drained the pond, pressure cleaned it, and within 3 days, the same thing. We had some water Irises in it, which were there when we moved in, but a new "pond guy" has since added some water hyacinths and marestail. However, we can't seem to clear the water and can never see the fish anymore. The pump circulates the water through the pressure filter and into a top basin, which drops into a second basin and over a small waterfall into the pond. I'm really at a loss as to why the water won't clear. The pond is smooth concrete, no rocks and we don't use a water softener (which someone told me was not good for fish ponds). Do the barley bales have to start getting mushy/rotting before they are useful? That's what the first pond guy told me, but even the large barley bale, which has been in the pond for about 3 months, doesn't seem to do anything. We also have some mint in the top basin. Help! There aren't any decaying leaves at the bottom, or anything else, so we just can't figure out what to do next. Neither pond guy recommended a UV filter, when I asked, and said to try with bio filtering first, but that hasn't seemed to work. Any advice would be very much appreciated, both by me and the fish!

  • chas045
    8 years ago

    If Dsolv9 and clarity max aren't very expensive, then I would like to congratulate you for finding pond people who weren't making an effort to rip you off; if they are, neverrr...mind. I have never had your problem, so I can't be of great help. However, we have often heard that the UV light thing will actually work on the pea soup type algae. As mentioned many times, I have an artificial stream that appears to be most of my filtration. Since you have a couple extra areas before your pond, I would suggest that you add more plants or allow ones already there to grow more to create large root masses. However, you would probably need to kill the pea soup first with the UV or something else. Hopefully, plant root masses would filter future crud. I have string algae and there is some evidence that it competes with the single cell algae types; so if you end up with some, don't remove all of it.

  • Sue Jimenez
    8 years ago

    Thanks for the advice...we don't have the string algae, just the pea green soup. I have read and heard about the UV light, but both of the pond guys were lukewarm about it, preferring instead to use plants, etc., however, after several months, that hasn't helped. I'm thinking that since it is getting colder, I will wait until spring thaw and see what happens. Then, I may invest in the UV, after having gone through a full year of fish pond issues. Thanks again!

  • gardnpondr
    8 years ago

    When you get enough plants in your pond the green water will just go away because they eat the stuff so to speak. Time and patience and lots of plants. No UV or anything is needed just plants. I don't even have a filter in mine and you can see the bottom. Half my pond is covered in plants and it's in the full sun all day.

  • Gloria J. Gabriel
    7 years ago

    I am new to this site and have been reading many of your comments to try to find a cure for my green algae problem. The comments here have been so helpful, and I now realize that I am doing many things wrong. I have a "pond" of about 1000 gallons. It is made with a new agricultural tank (poly-hard side tank) with the top cut out. I started it last year and finally got it in pretty good shape, but this spring, I have pea soup! I took the rocks out (permanently), did a complete cleaning and water change, and cleaned the filters thoroughly. It stayed clear for about 3 days and algae started again. I now have slightly cloudy water that is a bright green. I thought I had tried everything, but you have given me great ideas. I am going to try the batting for filtration and will put some AC in the waterfall to help clear it.. A couple of questions:

    1. Will duct (or is it duck) week give me a quick cover until I can get bigger and better plants going?

    2. I have plecostomus, Koi and goldfish in the pond. Will it hurt to add catfish to help with cleanup?


    Thanks to everyone for your information!


  • Sue Jimenez
    7 years ago

    Well, we have now been through all 4 seasons with our 900 gallon pond, with goldfish, and are on the third "pond guy" (they keep disappearing!). After seeing the dynamics of the pond, and more consultation, the suggestion seems to be (the pond is pea green once again and has remained that way since spring thaw) the following: the pump, which was in the pond when we purchased the house and is still there, is insufficient to keep a good water flow throughout the pond, so we are going with a higher GPH to help. Also, we are going to try the UV clarifier (which I had already purchased but was afraid to install myself), add more water lilies and a few more plants. Our pond is in an outdoor courtyard, but there is only one small tree, which even in full bloom, doesn't provide much shade and part of the problem is that the surface of the pond is exposed to full sun much of the time, creating perfect conditions to generate pea green water. Hopefully, after these adjustments, we will get rid of the green and be able to see the fish again. Another suggestion was to have a couple of container trees, which can be moved around the pond to provide shade, such as a Japanese Maple, etc. Unfortunately, Japanese Maple shed their leaves (which would fall directly into the pond), and are wind-sensitive, which is a problem where we live. The courtyard is large enough that it generates its own micro climate, including a wind tunnel! Best of luck and hope we can all have a pea green soup free pond this year!



  • mckool
    7 years ago

    aereation will help - run 24hrs for as many days as needed, and plenty of plants. I suspect at least a 14-16 inch air stone - check with one of the manufacturer's or major pond shop on-line to get an estimate for the CFM that will be needed. I use mine 4-6 times a day for 30 minutes to supplement the air in my 800g pond. I think mine is about 1 CFM. Benenite will also clear green water - it's hard to use as you need a blender to make a fluid paste then add into the water stream.

  • Andrew Miller
    7 years ago

    Pond filtration system. Koilady, per your offer, I'd like to receive a copy of the plans for your filtering system. No matter what I've tried, I also cannot keep my 5000 gallon pond clean. Send me a private message and I'll reply with my email address. Thanks

  • chas045
    7 years ago

    Andrew: This is a very old thread. I don't think I have seen koilady here for several years. However, I did a search and found this link about koilady's filter system. Perhaps it is what you are looking for.

  • Sue Jimenez
    7 years ago

    Since my post in April, the pond has greatly improved. We had a larger pump installed to get the water really moving, and that, combined with the UV clarifier have made a huge difference. Also, we added more water lettuce, water hyacinths and some Irises and waterlilies. There is a lot more shade, which also helps. We also added about a dozen snails and they also help to keep the algae down. All in all, we're 5 weeks into since the reno, with temps in the mid to high 90's and lots of sun, so I think we've finally figured it all out.....even the fish seem happy (at least I think they are....I could barely see them before to tell!) Thanks for the help and suggestions

  • jodeesiff
    7 years ago

    Hi Koilady,


    I know this is a super old post, but, I was wondering if you are still willing to share your diagram. We had a pond built last summer (we live in Tucson) and unbeknownst to me he put NO filter in it. I really need help on how to save our pond and our fish. Thanks in advance for your help.

  • chas045
    7 years ago

    jodeesif; Did you not see my link at the word 'this' in green one post up?

  • jodeesiff
    7 years ago

    No, I didn't look down that far, Thanks a lot!

  • PRO
    WaterfallNow
    7 years ago

    Is it possible that your pond is too small? Depth and surface area can play a role in the ability to keep your pond nice and clear so you can see the bottom.


    Tips to Get rid of algae in a pond

  • mckool
    7 years ago

    really need to start a new thread, not sure who WaterfallNow is addressing

  • bernardakl
    7 years ago

    Try placing filter carbon in your filter and adding a UV light to your system.

  • Michael N
    6 years ago

    I don't usually join these sites, but this thread changed my mind. gknee, I was having the same issues, brown nasty water with a nasty odor. I did take my skimmer net and clean the bottom as best I could, drained about a third of the water and refilled. Now it was even worse, like chocolate milk. So I tried what I read in a few replies, bought a large trash can, drilled about ten holes in the bottom, stuffed it about half full of pillow and quilt fabric, (also drilled 3 holes near the top for overflow), rerouted my waterfall feed into the trash can, hung the drilled section over the edge of the pond, plugged it back in and went to bed. To my amazement I woke up this morning to a crystal clear pond and happy fish. I still can't hardly believe how crystal clear it is. My pond and number of fish are about the same as yours. To everyone here giving good advise, thank you!

  • PRO
    it'sALLart
    6 years ago
    last modified: 6 years ago

    Yup, this is an ancient thread, but very helpful. I had to give up the pond eventually as we were starting a new house build and that summer the (really old) liner developed some big cracks due to age. Gave my two humongous koi to a local pond supply place and removed the pond. I figure the house will sell easier without something future owners may look at and think "high maintenance" (not that they're wrong, but...) and I want to ditch the old house fast when the time comes.

    I write this post simply to say to new pond builders:

    When you buy a pond liner, get a REALLY GOOD UV PROTECTED one that is mostly thick rubber, not plastic. I thought mine was thick enough but after 12 years or so, it started to wear out due to sun, get brittle and just start having problems. You drop a rock? Oops, hole! Now the pond area is just a plant area and all I have are memories of better pond days. I'll have a pond at the new place after things settle down and thanks to many posters here for all the info to help keep the water clear when that time comes!