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5 Types Of Pond Algae You Can Find In Iowa

Pond algae are the most unappreciated part of your pond’s ecosystem.

Wait, isn’t algae actually bad for ponds? Well yes, too many algae are definitely bad. It looks horrible, kills your pond, and can smell really bad.

But in the right amounts, it won’t hurt your pond.

The 5 most common types of pond algae include green water algae, string algae, blue-green algae, euglena, and Chara. Some of these are deadly for ponds while others can actually help make it better. They add oxygen to the water, feed animals, and some can even do more.

You should be aware that they can all grow insanely fast if not dealt with properly. We’ve seen plenty of our client’s ponds filled with algae, and it isn’t good.

Clients tell us it turns their beautiful pond paradise into an embarrassing eyesore:

floating algae bloom

Nobody deserves that, and you don’t have to let it happen to your pond.

Your first step, as it should be with most anything, is to learn what you are dealing with. Knowing what you are facing can help you prepare for it and even prevent it from ever happening.

If you want that, keep on reading.

You can read about our pond cleaning and maintenance services >>

1. Green Water Algae (planktonic)

You actually will want some of this type of algae in your pond, it makes it healthier! Well, in small doses.

Green water algae provides oxygen, nutrients, and is a food source for ponds and pond animals. It also provides shade for the pond bottom to keep nuisance plants from growing easily.

It’s when the nutrients get out of balance that it becomes a problem.

Green water algae as one of the types of pond algae

You can tell when planktonic algae is out of control because your pond water will turn pea green (think The Exorcist).

But you’ll never see it coming.

These little microorganisms aren’t a problem until they are, so you need to make sure your pond’s water stays in balance. Otherwise, you’re pond could end up brown, green, blue-green, or somewhere in between.

You can prevent green water algae with good filtration and maintenance.

Just like with our next type of pond algae.

2. String Algae (filamentous)

Yep, it’s your pond’s bad hair day.

This type of pond algae is also known as pond scum or moss, mostly because that is what it looks like.

String algae as one of the types of pond algae

You’ll see string algae as it rises to the surface of your pond in long, wavy mats of green. It’s like someone put a blanket over your pond, but not in a good way.

Your pond will suffer if there are too much string algae, but a little is good for your pond. It helps to oxygenate the water and feed any pond animals.

But too much can clog your pond’s mechanics, block sunlight (and your view), and in general lower the water quality.

When looking for this, check near the edges and bottom of your pond. They start growing there and then rise to the surface over time.

Prevention is easier than removing it, just like with green water algae. You should have plenty of beneficial bacteria added to your pond, rake out any string algae that start showing up, and monitor your water quality.

If you do those, then this type of pond algae shouldn’t be a problem.

3. Blue-green Algae (attached-erect algae/cyanobacteria/oscillatoria)

This one does have a lot of names, but that’s because it isn’t your run-of-the-mill algae.

It comes in plenty of colors, such as blue-green, red, brown, and yellow. Each one is just as bad for your pond as the last.

Blue green algae bloom starting in a pond

Your water quality is what causes this type of pond algae to appear. Poor filtration, too many fish, and not enough oxygen are just a few examples of what can cause blue-green algae blooms.

It’ll also make your pond smell bad, like dead fish bad.

Do not touch the water if you believe you have an outbreak. Cyanobacteria can make you sick if you touch it.

While it sounds bad, remember that this type of algae is good for your pond in moderation. It occurs naturally in ponds everywhere and Mother Nature tends to know what she’s doing.

4. Euglena

You don’t really need to worry about this type of pond algae if you have a koi pond. But, that doesn’t make it any less of a pain to deal with.

Euglena appears suddenly as if it were waiting for the perfect time for you to be inconvenienced. You may be scared as it does tend to come in crimson red and is toxic to plants and animals.

Cleaning it out is a pain because you’ll need to either drain the whole pond or use chemicals to kill it off. The chemicals can be harmful to fish and plants too, so we recommend the drain and clean.

A drain and clean is also a great time to inspect your pond for anything that isn’t working or will need replacing soon.

Check out our leak detection and pond repair service for more information

You can help prevent this by using an Ion Gen, which helps balance out your water with naturally occurring copper (which fights algae).

On the other side of algae is Chara, which is surprisingly good for ponds.

5. Chara (muskgrass)

You’ll be able to tell why people call it muskgrass when you smell it. It’s kind of garlicy, hence muskgrass.

This is a tricky type of pond algae because it looks like a plant.

Chara algae bloom underwater

But even though it may be trying to trick you, it’s helping out your pond at the same time. Animals eat it, it filters pollutants, oxygenates the water, and helps hold down sediment that can cloud the water.

You shouldn’t let it grow too much or it will take over your pond.

If anything, you could start doing some underwater farming and cultivate it to make your pond even more amazing.

Keep All Types Of Pond Algae In Check

No matter what it looks like, all types of pond algae look bad when they get out of control. You can keep your pond a paradise with frequent maintenance and regular checkups.

You can use these 5 ways to better control algae >>