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Ecosystem ponds are easy to care for, but bad algae can happen to good water features. Here’s what you need to know.

What Are Algae & Are They Always Bad?

In mid-to-late spring, sunlight and air temperatures start warming pond water. Plants will start to thrive – but they aren’t the only aquatic organisms hitting their stride. These conditions are also great for algae.

Despite their bad rep, algae are actually a necessary part of an ecosystem pond. Having algae or biofilm growing on rocks and gravel is good. It breaks down extra nutrients in the water and acts as a filter. But if left unmanaged, algae can get out of control. Here’s what we recommend if that starts happening in your pond.

Five Ways to Keep Algae at Bay

1. Drain and Clean

First, if you haven’t had an annual drain and clean, we recommend starting with this step, especially if your pond wasn’t netted in the fall. A proper drain and clean will remove decomposing debris such as fish waste, plant matter, and leaves from the pond. This gunk is full of nutrients that algae find delicious.

2. Beneficial Bacteria

Next, be sure you are adding plenty of beneficial bacteria to your pond. These microbes eat excess nutrients in the water, taking food away from algae. A healthy population of beneficial bacteria in the water will essentially starve out algae and keep them from spreading.

Beneficial bacteria cultivate in biofilters and on rocks and gravel inside the pond. They thrive in water with lots of oxygen and will multiply quicker when water temps start rising above 75 degrees. For ponds being treated in early spring and fall when temps are cooler, we recommend using cold water beneficial bacteria to keep the ecosystem in balance.

Adding beneficial bacteria is especially essential after a pond is cleaned. It’s usually best to follow the instructions on the label of the product, unless instructed otherwise. If you accidentally overdose a treatment or two of beneficial bacteria, it’s usually not an issue because most strands are non-toxic and safe for fish and pets. If you find that you keep forgetting to consistently add beneficial bacteria to your pond, try an automatic dosing system. This device acts like a drip IV bag that automatically adds treatments to the water. Just change the bag about every three to four weeks. Then, set it and forget it!

3. Aeration

Since bacteria thrive in water with lots of dissolved oxygen, the more turbulence and moving water at the surface of the pond, the better. Most ecosystem ponds are installed with a waterfall that cascades into a pond. This is a highly effective way to add dissolved oxygen, plus it adds beauty and the sound of running water to the environment.

In ponds with no waterfall or in larger bodies of water with dead zones (areas where water is stagnant or moves very little), add a pond aerator or a jet. These will disturb the water surface and can be an effective way to add oxygen.

Remember that oxygenation happens when low-oxygen water contacts the atmosphere (air). Oxygenation doesn’t come from the bubbles from the aerator. That’s why agitating the water’s surface is important to saturate and cycle oxygen throughout the entire pond.

4. Proper Fish Feeding

Many pond enthusiasts have been trained by their fish. It’s true! Many people feed their aquatic friends every time the fish start sucking their little mouths at the surface. As satisfying and entertaining it is to watch your fish eat, remember that more food means more fish poop – and fish poop is food for algae.

If you feed your fish a heavy amount and there are excessive algae in your pond, try cutting back on the fish food. As hungry as they may seem, your fish can go weeks without eating, so there’s a chance you are over-feeding the already. Sometimes hungry fish will turn to alternative food sources and start eating algae in the pond, too.

5. Ion-Gen

For ponds with string algae (hair-like long strands of algae), an Ion-gen may be a good option. This last-resort option is often necessary for eliminating excess growth.

An Ion-gen releases copper ions into the water. This kills string algae. Copper levels in the right balance are safe for plants and fish. However, do not leave the ionizer on a high setting for long durations (over a week) because that can make water levels toxic to our finned friends. If the water is cloudy or looks like pea soup, an Ion-gen will not be effective in getting rid of this type of algae. Good filtration, water circulation, beneficial bacteria, and aeration should treat suspended algae blooms.

Keep Your Ecosystem Pond Balanced

At Good Earth Water Gardens, our main objective is creating a balanced ecosystem that works with Mother Nature – not against her. Most of these algae solutions are not instant fixes. It can take a few weeks for a pond ecosystem to come back into balance. But with consistency and a little patience, you’ll have a healthy, beautiful pond. And if you need help, we’re just a call away.

The pond pros at Good Earth Water Gardens can help you establish and sustain a thriving pond ecosystem. Give us a call at (816) 720-7577 or submit an online form. We’d be happy to speak with you about your needs.