You finally got that beautiful, relaxing koi pond built. To keep it looking that way you will need to maintain it. Algae is one of the problems you will have to tackle.
So do you know how to get rid of algae in a koi pond? Plan and build your pond in a well-shaded area. Put your pond where it is covered in about 65-70% shade. Purchase a pond skimmer. Have plentiful plants around like pond lilies. Use a net or pond brush on your pond regularly. Use pond dye in your water to dilute the amount of sunlight
Every Spring pond owners all have to deal with algal blooms flourishing. This is because of the warmer temperatures, sunlight, and plentiful nutrients from dead plant matter and fish waste fuel the algae growth. You need to have some idea about what kills algae in order to eradicate it? As you see above, this isn’t nearly as complicated as you probably think it is as I like to keep things simple.
Things That Inhibit Algae Growth
There are many ways to keep that algal blossom from blossoming
- Shade-When you decide to build your pond find a shady spot. Like I mentioned above, direct sunlight is what gets algae growing out of control.
- Special Algae Brushes-There is special brushes you can use to skim across your pond to collect all the algae and other debris. Brushes like the Pond H2O Pool Brush can be swiped across your pond to collect the algae on it.
- Algaecide-Places sell algae killer for your pond. Some are for pool use and I’m not sure if the ones for a pool are safe for a pond filled with expensive fish. So find one for pond use. AquaShade Organic Plant Growth Control is a good product to use.
- Koi- Your Koi love to eat algae too. They eat all plant life around them and a lot of bugs. They are little hogs.
- Nets- You can also use a net over a brush if you want. It will do the same job. Just don’t scoop up your fish as I imagine they probably don’t like it.
- Check Your Ponds pH Level- When you lower the ph in a koi pond you are at least allowing the live good string algae without killing it and allowing the dead algae matter to float around wreaking havoc.
In Spring And Summer, You Can Guarantee Algae Will Happen
Algae like that sunlight stuff. Like plants, algae need sunlight to convert the carbon dioxide in the air into organic compounds, especially sugars. And when is the sunlight the brightest and most abundant? You guessed it. Summer
That is why your pond gets green or brown looking during this hot time of the year. It’s doing your fish a huge favor though when it’s alive. It provides much-needed oxygen to your marine friends. Your koi also eat algae as a food source too.
So it serves many positives purposes, but you got that Koi pond built to see your fish and that algae are very effectively preventing that. A murky, gross mess is what you see.
Who Wants Pond Algae?
Once algae die it depletes the amount of dissolved oxygen in the water which could be helping your fish thrive. String algae contribute to producing more oxygen and build up oxygen bubbles that get caught in it’s “hair”. So string algae aren’t all bad besides taking up your whole pond making it unsightly. Anything that improves oxygen growth can be good news for koi.
Unfortunately, this same string algae that were semi-healthy for your fish in this form will soon die and whither sinking to the bottom. It then gets broken down by bacteria using that same oxygen to do so. So living string oxygen promotes more dissolved oxygen. Dead string algae take away the oxygen in the water.
A Koi pond owner sure doesn’t want it. You want to be able to sit on your patio, relax and watch your Koi swim around happily. That pesky algae bloom makes it impossible to do that. It sure doesn’t take long to take over either. Like overnight it seems.
It starts to use up a lot of oxygen once it dies and rots. Your pet fish need that oxygen to thrive. So you need to manage it as best as you can.
Why Does Algae Grow In The Winter And How?
I actually wouldn’t mind seeing algae in the winter as I ain’t going outside anyway in that cold air. Not if I can help it anyway. Why doesn’t algae show up in the Wintertime instead of the inconvenient Summer?
Algae do grow in the winter, but it doesn’t overtake things as it does in the summer. You don’t have to worry about it as much. I would prefer it to be around in the Winter more so I could enjoy the crystal clear water and my Koi Carp swimming around happily. The Koi won’t eat in the Winter because of a slowing in their metabolism which means Winter does not provide the best temperature for Koi to gorge on algae blooms.
Some traits of Winter weather on a pond are more advantageous for pond algae. Algae feed on byproducts of decomposing organic matter and debris. In warmer weather, bacteria consume these byproducts and algae doesn’t get as much of it.
As it gets colder, however, the bacteria become dormant. That leaves a decomposing-byproduct-all-you-can-eat buffet for the Winter algae to consume. The combination of a little light and all that decomposing matter the algae have all they need to thrive.
What Can You Do?
You can do what you can to limit the sunlight that algae has access too by putting pond dye in your Koi pond. This dye also gives your water an attractive bluish hue. Without light, the algae can not go through Photosynthesis so it can’t grow.
Have a pond skimmer installed. Pond skimmers are mechanical filters that feature some way to catch debris as water flows through it. Including algae.
Keep your pond pump pumping. Keep the water moving so it doesn’t become still and stagnant. Algae love stagnant water full of all kinds of dead matter to feast on. The pond pump also keeps oxygen circulation for your koi fish.
Now Your Ready To Conquer Algae Overgrowth
Following these tips will keep your pond from being overtaken by algae running amuck. Pond pumps, pond dyes, and skimmers are all really helpful when it comes to tackling your algae problem. Don’t use chemicals if you have fish in your pond. No pool algaecide or anything else that may contain ingredients that could be harmful to your fish.
Also, keep in mind the benefits that algae provides for your pond, fish, and ecosystem as well. During the photosynthesis process, the resulting oxygen can be saturated into the water for your Koi giving them breathing room. Koi, like any other fish, have to have their oxygen from the water and not the air.
Plan to build your pond in a shaded area to keep it out of the sun. Preferably you would have a building or some structure providing most of the shade instead of only trees. I say that because you don’t want a lot of leaves and debris falling in your pond and just rotting. Strive to have at least 70% of your water in shade. Your koi will have it made in the shade.
Are algae beneficial in any way? Algae when it is still alive definitely has its benefits. The oxygen that it supplies in the water alone is a great help to giving your koi some air. It’s also a food source to your koi in the summer. Planktonic algae, for example, make up the first link of the food chain for other organisms that are food to the fish.
What chemicals can you use on a koi pond? The chemicals you use in your pool sometimes don’t translate over well to using in a koi pond. TetraPond Algae Control is a good choice. Nualgi Ponds is another popular one that is safe. Anything chlorinated should NOT be used. Most pool products contain chlorine which is bad for fish. Pond dyes are another thing used to inhibit sunlight which algae blossoms need to live and an added benefit is the awesome blue hue it gives your water.
Are green algae plants? Algae are not considered plants because they are just aquatic. They can’t survive on land.
Can algae harm fish? That depends on the type of algae. Just like plants, some algae are toxic. A small number of algae types are poisonous and can cause harm but not many. Even with the harmful ones many just have negative effects. Consider the fact that plants, for the most part, are really healthy for us. Poison ivy, however, will make most people itch and have a rash. A few algae here and there generally have terrific health benefits just like described above. It’s just when it starts to overtake everything where it becomes a problem.
Do you have a method for killing off algae growth? Let me know in a comment if you have a cool way of keeping your pond algae-free. Thanks for visiting.
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