Algae. It’s a normal part of a pond ecosystem but nobody wants to look at green water or host a summer barbecue with friends beside a fuzzy pond.
It can be frustrating to deal with but the trick is not to try to rid your pond of algae, but to work with its natural behavior and the environment of your pond to create a balanced ecosystem that is both healthy and aesthetically pleasing.
Here are some things to know about algae, why you need it more than you think, how to avoid overgrowth and what to do when it starts to look unpleasant.
All Algae Is Not Created Equal
There are actually two types of algae that look and behave differently, so it’s helpful to understand what you’re dealing with.
One type is suspended algae. This is the growth that you typically see in the spring when your pond is coming back to life. It appears as temperatures rise but before your fish have become active, which makes it the king of the pond. With no competition for food, it thrives nicely.
This type of algae will usually disappear after a few weeks.
The second type is string algae. This one is the real villain – both an eyesore and a nuisance, it’s pretty tenacious, can last all season and happens for a variety of reasons that can be tough to pinpoint.
You’ll see this type growing on your rocks, plants and any surface it can attach itself to.
Understanding what you’re dealing with can help you choose the right way to handle it.
An Ounce Of Prevention Is Worth A Season Of Cure
As with many things, from the flu to an overheated car engine, prevention is the best way to deal with algae.
Preventing algae starts with a balanced pond ecosystem that includes these vital elements: plants, fish, rocks and gravel, and filtration.
Let’s take a look at each of these briefly to see how they can help you stop algae before it takes hold.
The Role Of Plants
In addition to beautifying your pond, plants play an essential role in consuming excess nutrients that algae might otherwise feed on. Without the nutrients it needs, algae cannot proliferate.
Other plants will oxygenate the water, which also contributes to a healthy ecosystem.
Still others, like water lilies, shade the pond and keep out the excess sunlight that algae is known to bask in.
Choosing the right combination of nutrient-consuming, oxygenating and shade plants will help keep algae away.
The Role Of Fish
These beauties do more than delight their humans. They also consume vast quantities of algae. Large koi are especially beneficial because they will forage and feed on string algae all day.
For maximum benefit, choose koi over nine inches long and let them act as natural vacuum cleaners.
The Role Of Rocks And Gravel
One of the benefits of rocks and gravel is to provide nooks, crannies and crevices for bacteria to thrive. That may sound counterintuitive – after all, why would you want bacteria proliferating in your pond?
Well, just like all algae is not created equal, neither is all bacteria. And while some can be harmful, others, like the type that nestles in between your pond stones, is tremendously beneficial. Think of this bacteria as the natural garbage disposal system of your pond. It will feed on the same nutrients, fish waste and plant decay that algae would otherwise feed on.
With that much competition for food, algae loses.
How Filtration Works
Systems like an automatic pond skimmer will help remove surface debris before it can sink to the bottom and decay, becoming food for algae.
Other systems, like biological filtration, will add beneficial bacteria to your pond that will have the same effect as the naturally occurring bacteria.
Either way, you’re eliminating the source of algae blooms, which is the excess nutrients that come from waste materials that are not removed properly.
Beware Chemicals And Outside Sources Of Nutrients
The nutrients that allow algae to thrive can also come from outside your pond. Two of the most common culprits are storm water runoff and lawn fertilizer. Each of these contains chemicals that can quickly flood your pond with the stuff of algae’s dreams – and your nightmares.
Allowing storm water to run off into your pond or fertilizing a nearby lawn that accidentally seeps into the pond can turn an otherwise healthy ecosystem green almost immediately.
Take the proper measures to avoid runoff entering your pond and if you suspect a chemical runoff as the source, your best bet is to protect your pond from this type of intrusion in the future.
My Pond Is Overgrown! Now What?
If you haven’t quite prepared and algae has made itself at home in your pond, don’t worry. You can still restore the balance.
First, check to be sure you implement the necessary preventative measures. These will begin to improve the overall health of your pond and help maintain it later. Ask yourself a few key questions:
Is the pond receiving too much sunlight? Consider adding shade plants to reduce algae growth.
Are you implementing proper filtration? If debris is either floating or collecting at the bottom, clean it out and put a skimmer or other filtration system in place.
Can natural bacteria thrive? Add gravel or rocks if necessary to encourage competition for algae.
Are you overfeeding fish? Excessive feeding can lead to the food being left to decay and also to excess fish waste, both of which can contribute to algae blooms. It may be fun for the kids to toss in the Koi Krunchies, but careful feeding is far preferable than daily feasts.
Is the water circulating? Still water is a boon for algae. That’s why waterfalls, bubblers and fountains are typically added to ponds – not only do they look and sound great but they keep the water moving and the oxygen circulating, which can help prevent algae.
Finally, consider a commercial treatment. These can help by adding naturally beneficial bacteria to your pond and contain ingredients that are safe for fish, humans and wildlife. Aquascape is one leader in pond treatments. If you need advice about which products to use for your needs, just ask – we’re here to help.
Algae: You Love To Hate It, But You Need It
Believe it or not, algae is more than just a nuisance. In excess it can certainly look ugly and even create an unhealthy environment in your pond. But that doesn’t mean you should try to eliminate it.
In balance, algae is one part of a functional, sustainable and healthy ecosystem. It provides a natural food source for fish, produces oxygen and reduces nitrites and phosphorous.
So before you let it drive you crazy, ask yourself whether your pond is healthy and balanced. If so, the occasional sight of green should be welcome.
Have more questions? Need help improving the balance of your pond or dealing with algae? Let us know!