Anyone know anything about koi ponds and algea I'm desperate to get my green pond back to normal ..its 3000 gall

Cathy G
by Cathy G
  26 answers
  • Douglas Hunt Douglas Hunt on May 03, 2012
    How many fish are in your pond, Cathy? Fish and fish food add nutrients to your pond, which in turn feed algae. So it's important that you do not have more fish than your pond and filter will support and that you don't overfeed your fish. How large is your pump? If you have koi, the pump should circulate the full 3000 gallons every hour.

  • Cheryl M Cheryl M on May 03, 2012
    Cathy I had a 2,600 gal koi pond for years and I learned many things. one thing about algie wont survive if the are no nutrients for it to live on so make your pond 75 percent water plants. The plants wont leave anything for the algie to live on. The plants work hard keeping your water clear and gives your pond the balance , your fish will love you for it.

  • Sherrie S Sherrie S on May 03, 2012
    Cathy G, I have a 2500 gallon Koi & goldfish pond. First thing is algae loves sun so adding 75% water plants as Cheryl suggested will be very helpful. All ponds go through the green look but should clear up naturally. Be sure you have good circulation throughout the entire pond and as Douglas said your pump should circulate the entire pond every hour. My pump outputs 45 gallons a minute or 2700 gallons an hour.

  • Cathy G Cathy G on May 04, 2012
    THANK YOU ALL FOR YOUR SUGGESTIONS ..I LIVE IN NORTHWEST PA.. and we still get frost here so i don't have any floaters on my pond yet but lots of marginals .. a couple more weeks to go before its safe to put in tropical s ..the problem is that its been unusably warm here for this time of year . i have about 20 koi and gold fish and some new babies ..and no i have not over fed them .. Ive tried algae clear different bacterias and all . this is my 5 year with my pond but this spring i had to replace the liner so i went bigger . ??

  • Cathy G Cathy G on May 04, 2012
    also my pump is big enough i actualy have two one for the water fall and one for the fountain

  • Walter Reeves Walter Reeves on May 04, 2012
    I think you have too many fish for the water volume. 3000 gallons should support around 15 six inch fish.

  • Sherrie S Sherrie S on May 04, 2012
    I'd stay away from most chemicals. In the 8 years I've had my pond I've only used one chemical from Ecolabs - called microblift PL. 100% natural and safe for all plants, animals and fish. Beneficial bacteria breaks down algae, reduces ammonia and nitrogen and improves oxygen levels. Use to seed and maintain biological filters and dissolve organic sludge and slime. Best used when water temperatures are above 55 degrees.

  • SawHorse Design Build SawHorse Design Build on May 04, 2012
    Don't they have fish that can eat the algae? I remember having "algae eaters" in our indoor fish tank

  • Sherrie S Sherrie S on May 04, 2012
    Yes Sawhorse. I have two algae eaters called Plecos. They would not live in PA as they are tropical fish and would die if the pond temp gets under 50 degrees.

  • SawHorse Design Build SawHorse Design Build on May 04, 2012
    That's too bad.

  • Micki N Micki N on May 06, 2012
    You can add Barley straw. Use chicken wire to make one or two round balls about 18 inches each, add barley straw to fill. Put them in the pond, change the barley straw once a month and no more algae.You can also buy liquid barley concentrate at most home centers. Best thing about is no chemicals, all natural. Works great, I live in Ohio and it works very very well. Took all my plants out this year, tired of not being able to see my fish. Took about 3 days to be all clear.

  • Sherrie S Sherrie S on May 06, 2012
    Micki N, Cathy G is in PA so maybe the barley straw and no plants could remove algae but I can't imagine a pond with fish & without plants as the plants provide food, oxygen and shelter.

  • Micki N Micki N on May 07, 2012
    Sherrie S Yes fish ponds can survive without plants as long as oxygen is added. Shelter is provided by the rock formations, and the fish are fed daily. Plants are around the pond providing shade thoughout the day, with never more than 60% coverage. Beautiful pond, all clear, can see all my fish. I love it and don't know that I will ever add plants back into the water again. Who knows may change my mind in another year or so. But for now I am enjoying the clear water and the beautiful fish for a while.

  • Cathy G Cathy G on May 07, 2012
    thanks micki ..i think i will try the barley straw and see how that works !!

  • Sherrie S Sherrie S on May 07, 2012
    I agree with barley straw since it is natural and does help. After your explanation of your pond I must agree with you. The only plants in my pond are lilies and anacharis which removes waste, and prevents algae growth. - all other plants are outside the pond.

  • Cathy G Cathy G on May 10, 2012
    thanks all ordered some organic barley and pond clarifier

  • Janet P Janet P on May 10, 2012
    we use a plant that floats to the bottom. Theyre ankored to the bottom, Oxinators, (sorry for the spelling). we use them. Ya need lotsa plants. The plants that float to the bottom begin with an A. Good luck. Try a pond store.

  • Tammy@Deja Vue Designs Tammy@Deja Vue Designs on May 12, 2012
    We have used the barley straw....and it worked like a charm!!

  • Sherrie S Sherrie S on May 12, 2012
    Janet P, I think your plant is anacharis and it is excellent for the pond.

  • Cathy G Cathy G on May 14, 2012
    my work in progress

  • Cathy G Cathy G on May 14, 2012
    its starting to clear up with a biological clearifier..thanks to all who responded

  • Douglas Hunt Douglas Hunt on May 15, 2012
    Great news, Cathy!

  • I Love I Love on Aug 27, 2012
    Hi im new to Hometalk and Im not sure if you have fixed your problem yet. this year being one of the hottest/ driest on record this is a common thing. depending on how your pond is set up and how you maintain it will effect your water quality. we preach using an ecosystem (plants, rock and gravel, fish, biological filtration, and mechanical filtration) It takes time for your pond to establish itself but eventually you can achieve clear water. even the pros are having difficulties this year I personally have struggled with water quality all summer. I would be more than happy to answer any questions you have relating to water features in the future.

  • I Love I Love on Aug 27, 2012
    to further explain the ecosystem. we try to work with mother nature and not against her. you need 1. circulation (a pump and waterfall, this add aeration and the changing of gases and keeps the water from becoming stagnant) 2. Filtration (includes the use of both a biological and a mechanical filter. A biological filter provides surface area for beneficial bacteria to colonize and remove excess nutrients from the water. A mechanical filter will not only pre-filter the water and house the pump; it will also skim debris from the water’s surface to prevent the accumulation of organic materials on the pond floor) 3. Fish (an integral part of any ecosystem. Unfortunately, fish are often seen as creating a maintenance nightmare. Contrary to popular belief, fish will actually reduce pond maintenance, as they graze on string algae and bottom feed from the pond floor) 4. Aquatic Plants (Mother Nature’s true filters. Plants are great for adding character to a pond by providing color and texture, but from a filtration perspective, they’re second to none. Thriving from the excess nutrients in a pond and depriving algae of its food source, the aquatic plants in a water garden, given proper coverage, are critical for the overall health of the ecosystem) 5. rocks, gravel, and bacteria ( a controversial element in the hobby for many years. Many enthusiasts have steered away from rocks and gravel out of fear that their system will become a maintenance nightmare. On the contrary, rocks and gravel will not only make your pond look more natural, they will also protect pond liners from UV light degradation and they provide tremendous surface area for beneficial bacteria to break down excess nutrients in the water and dissolved organic debris on the pond floor) Having all these things in place makes all the difference in the health and success of your water garden. Use them and work with Mother Nature, not against her, for a chemical-free wonderland of water! The truth is that most people opt for the ecosystem way of water gardening because it’s easier and it just makes sense. A low-maintenance ecosystem pond provides you with more free time to enjoy friends and family … while gathered around your pond, of course!

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  • Penny T Penny T on Dec 03, 2012
    I built my filter from plans found at it's an outstanding filter and cleared up my 3000 gallon pond in a few weeks. I'm a heavy DIYer and got tired of spending money I don't have on things I can make.