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The Most Common Pond Problems – and How to Fix Them

    Keeping pond healthy in summer, high temperaturesImagine kicking your feet up at the end of a long day and sitting with a glass of lemonade next to your own backyard pond. A fluorescent orange koi greets you, waiting for his evening snack, and you watch a yellow swallowtail butterfly flit across your pond’s purple pickerel.

    You close your eyes, and you hear nothing but the sound of a flowing waterfall.
    That’s how owning a pond should be – and it usually is.

    This troubleshooting guide will walk you through everything you need to know about dealing with common pond problems and show you how easy it is to enjoy crystal-clear water and happy, healthy fish in your backyard oasis.

    IN THIS GUIDE: Troubleshooting Common Pond Problems

    Preventing Problems with Good Design

    Here’s the truth when it comes to pond design: Trying to save a few dollars here and there will cost you in the long run.

    You can prevent most pond problems by using the right materials and design from the start. That means either hiring an experienced professional to do the work for you, or investing in a quality DIY kit.

    Here are the elements that we’ve found make for a low-maintenance pond:

    • skimmer that removes 80 to 90 percent of the physical debris that enters your pond.
    • biofilter that has lots of nooks and crannies where beneficial bacteria colonize. These bacteria help keep your water clear. The water runs up through the biofilter then out through your waterfall.
    • Fish-safe EPDM liner that keeps water where it’s supposed to be: in your pond.
    • Heavy-duty underlayment that protects the liner.
    • Gravel on the bottom of the pond that gives beneficial bacteria another place to colonize.
    • stepped-shelf design that gives you a place to add plants, and your family and pets a way to safely enter and exit the pond.
    • Fish caves that give your fish a place to get out of the elements and away from predators.

    How to Keep Water Clear

    Get Rid of String Algae in PondAlgae, muck and murky water.

    They’re the most common complaints we hear from pond owners. Luckily, you can solve most issues with good filtration, beneficial bacteria and plants.

    We feel so passionately about crystal-clear water that we’ve created an entire guide dedicated to walking you through every possible cause of – and solution to – any water clarity issue. Check it out here.

    How to Fix Water Loss

    Pond leaks are much less common than people think.

    Based on our experience responding to countless reports of “leaks,” the source of water loss is often something much easier to treat than a hole in the liner.

    If you’re losing water, rule out these other potential causes before scheduling a leak repair:

    • Evaporation: Ponds can lose several inches of water very quickly in the heat of summer. A pond with lots of large, splashy waterfalls will lose even more.
    • Debris Build-Up: Check for dead leaves or other debris at the top of your waterfall.
    • Runaway Liner: Look for areas where the top of your liner has been pushed down.

    If you feel like you’re losing more water than you should be, and you’ve ruled out the causes above, try running what we call the 24-Hour Test. Here’s how it works:

    1. Unplug the pump.
    2. Fill the pond to the full level and take a picture.
    3. Leave the pond sitting at a full level without the waterfall running for 24 hours.
    4. Note the water level after the 24 hours. Take a picture.
    5. If the water level does not change, then we can assume that the issue is not in the pond itself but rather the stream, waterfall or plumbing.
    6. If the water goes down, then we know there is a problem with the liner. We want to let it keep dropping until it stops. Wherever the water level stops is where your hole is. Now, you can call the pros or buy a liner repair kit and get your pond back on track.

    Need more help? Read our detailed guide on finding and fixing pond leaks

    How to Fix a Clogged Pump

    The pump in your Ecosystem Pond should rarely, if ever, clog. That’s because the skimmer pulls out most of the physical debris before it has a chance to cause a problem.

    If a piece of mulch or other debris does manage to sneak past the skimmer and into the pump, you can fix the problem pretty easily:

    • Remove the check valve from the top of the pump.
    • Remove the volute cover (depending on the pump, you might need a flat-head screwdriver to pry it off).
    • Clean any debris off the volute cover.
    • If your pump has an interior baffle, remove and clean it.
    • Clean the top and inside of the volute chamber with your finger or a screwdriver.
    • Reassemble the pump and check valve.

    Need more help? Read our detailed instructions for unclogging a pond pump

    How to Get Rid of Duckweed and Watermeal

    Duckweed and watermeal are the world’s smallest seed-producing plants. While not necessarily harmful to your pond – some people add them as a fish snack – their fast-spreading nature can make them a nuisance for people who want to see their fish.

    You have a few options if you want to remove duckweed and watermeal from your pond or lake:

    • Prevention: Use Beneficial Bacteria and sludge remover to take out excess nutrients in the water. These nutrients ultimately feed duckweed and watermeal.
    • Aeration: A properly designed aeration system uses air bubbles to push the watermeal and duckweed to the edge of the pond. You can then easily remove the plants with a net.
    • Chemical Control: Broad spectrum contact herbicides are available and can quickly kill any part of the plant they touch, but you may need to use multiple treatments throughout the season.

    Learn more about controlling duckweed and watermeal

    How to Keep Fish Healthy and Safe

    Relaxing Ecosystem PondPond fish are some of the easiest pets you’ll ever own. Just give them a little food and shelter, and your koi and goldfish will reward you with hours of entertainment as they flit around your pond.

    Like any animal, though, fish can fall victim to illness or predators. Check out our Ultimate Guide to Pond Fish Care for all the information you need to keep your finned friends happy and healthy.


    If you landed on this article before you started building a pond in your own backyard, you’re already well on your way to preventing green water, string algae and leaks.

    A well-built Ecosystem Pond will have a biofilter and skimmer installed from Day 1, preventing green-water algae and keeping your water crystal-clear. It will have plant pockets and shelves where you can tuck in pickerel, cattails, waterlilies and all those other string algae-preventing plants, and a sturdy fish-safe EPDM liner protected by heavy-duty underlayment.

    See how we build our ponds at Splash

    Most pond problems arise when builders – professional or DIY – leave out one of these crucial elements. The best way to avoid these mistakes is to educate yourself before you dig (or hire someone to dig for you.)

    At Splash, we’ve been designing and installing low-maintenance, eco-friendly ponds for 30 years. Let us help you find the perfect DIY pond kit to get your project started on the right foot, or visit us at 1298 Toronita St. in York, PA to learn about our professional design and installation services.

    Learn More about DIY Pond Kits

    See Pricing for Professional Pond Installation