How To Get Crystal Clear Koi Pond Water

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How To Naturally Clear Pond Water Without Harming Fish

Keeping pond water clear the natural way is easy, and you'll be able to enjoy your pond again in no time. In this post I will show you exactly how to get rid of pond algae and muck, without using any harsh chemicals!

How To Naturally Clear Pond Water (kill algae without harming fish!)

One of the biggest frustrations of having a backyard garden fish pond is not knowing what to do when the water becomes mucky, green, and gross!

Don't worry, there is a simple way to naturally clear pond water without using toxic chemicals.

Below I'll give you all the details of how to clear pond water, and keep it clear safely, without harming your fish or plants!

Here's what you'll find in this detailed guide…

Help! What's Growing In My Small Garden Pond?

Last summer my little garden pond was overcome with a mossy, weedy growth. The pond water looked green, cloudy and disgusting.

After doing some research about small pond care, I discovered that the green stuff growing in my pond was string algae. Yuck!

Turns out that string algae growth in ponds is a super common problem.

Why You Want To Get Rid Of Pond Algae ASAP

Not only does it look terrible, but algae growth in ponds is bad because it can take over a small pond quickly. When left to grow, pond water algae can eventually starve the fish and plants of necessary oxygen and nutrients.

I was pretty nervous when I first started reading about algae in pond water.

Mainly I was worried that I'd have to use expensive chemicals for clearing my pond water. Plus, those chemicals might kill my fish and plants… or, even worse, it could cause me to have to start over from scratch with my pond.

Needless to say I was thrilled when I discovered that there is a home remedy for pond algae control.

As it turns out, clearing out garden pond algae naturally, and keeping pond water clear is easy. Whew!

Small bales of barley straw pond treatment

How To Clear Pond Water Naturally

It sounds strange, but the answer to natural pond algae control is barley straw.

Not only is barley straw a natural pond algae killer, but it won't harm your fish or plants – and it's cheap to buy too.

In fact, I've read that barley straw is a more effective pond algae remover, and it works better to clear pond water than expensive chemicals.

Win, win, win, win!

Fish swimming in clear pond water

You can find technical explanations on the internet for why barley straw naturally clears pond water.

But basically, as the barley straw decomposes it releases something similar to hydrogen peroxide (H2O2) which will eventually kill pond algae.

Whatever the technical reason is, it works great for treating pond algae!

Making small bundles of barley straw to remove my pond algae

Natural Pond Algae Treatment Use Tips

You can buy barley straw for algae control in ponds at your local garden center, or on the internet. You can also buy it in liquid form, or you can get the pellets.

When I bought mine, it came packed in small bales that were much too large for my pond (pictured above).

The package says that each bale of barley straw will treat 1000 gallons of water.

My small garden pond holds only 90 gallons of water. So I made smaller bundles out of the mesh packaging the barley straw bales came in when I bought them.

I used twine string to tie the opening in the mesh closed, and also to hang the bundle from my pond waterfall.

Tying my barley straw bundle before putting it into the pond

It's best to put your barley straw bundle in the pond near a fountain or waterfall where the water will flow through it.

Once the straw starts to decompose, the bundle will sink so it's no longer visible on top of the water.

Keep in mind that controlling algae in ponds using barley straw will take a little longer than it would with chemicals.

It takes a few weeks for the barley straw to begin to decompose and start clearing the pond water.

So, if you want to start seeing clear water faster, there are a few steps you can take now with these easy pond maintenance tips.

My barley straw bundle at the bottom of the backyard ponds waterfall

Easy Tips To Clear Pond Water Faster

Step 1: Manually remove algae from fish pond: To speed up your garden pond algae control efforts, start by manually removing as much of the algae from your pond as you can.

Don't worry this sounds harder than it is.

An inexpensive toilet brush works great for getting rid of algae in a pond. You can remove the algae by scrubbing the sides of your pond with the brush.

Ideally, you would buy a new toilet brush to use specifically for your pond; what would be more disgusting – using an old used toilet brush in your pond, or using your pond brush in your toilet!?

Removing pond algae with a brush

Step 2: Rinse your garden pond filter daily: If you have any type of pond water filter system installed, rinsing the filter daily during this time will also help to remove pond algae faster.

If your pump didn't come with a filter, I highly recommend you get a universal pond pump filter box. It will make keeping your pond water clear (and general pond maintenance) so much easier!

Or you can make your own DIY pond pump filter box using these super simple step-by-step instructions.

Rinsing my pond filter to help clear the water faster

Step 3: Use hydrogen peroxide (H2O2) to help clear pond water: Another thing that works great for algae control in fish ponds is hydrogen peroxide (and no, it won't kill your fish!).

I don't know if there's a special formula of H2O2 per gallon of water, so I recommend doing some research for your specific pond size.

My small pond is 90 gallons, and I added a 1/2 cup of H2O2 to the water. Pour the H2O2 over the running water of a fountain or waterfall to disperse it.

Using hydrogen peroxide to kill pond algae

Shortly after adding the H2O2 and barley straw to my pond, and following these steps to clear my pond water faster, I started to see results.

In no time, my pond water was crystal clear, and it stayed that way all summer.

Sparkling clear water in my front garden pond

How To Keep Pond Water Clear Naturally

Now I put a new barley straw bundle in both of my little garden fish ponds in the spring as part of my regular small pond maintenance schedule.

Since doing this, I've been able to avoid algae growth in my ponds, and keep the water clear. One small barley straw bundle lasts all summer.

Another thing I make sure to do as part of my regular fish pond maintenance tasks is to remove the leaves and other debris from my pond.

My pond skimmer net makes this task super easy! Regular pond maintenance is very important to ensure the water stays clear! Learn how to properly clean your pond here.

Using my skimmer net to remove leaves from my pond

If you're having problems keeping your pond clear, and algae growth is not the issue (or if you're not sure what the problem is), then I recommend testing the water.

You can get an inexpensive pond water test kit that is specifically made for testing pond water, and that will help you figure out exactly what type of treatment the water needs.

Testing my pond water with a kit

I love my garden ponds again now that I the water is clean. It's nice to be able to watch my fish swimming around in the crystal clear pond water, feeding on worms and other bugs that fall into the pond.

Plus my ponds are constantly filled with frogs and salamanders too – a wonderful sign of a healthy pond!

Related Post: How To Winterize A Garden Pond Step-By-Step

Frogs enjoying my healthy pond

Keeping pond water clear and algae-free isn't that difficult when you know how. Once you have it cleared out, it will be much easier to maintain it too – and you'll love your garden pond again!

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Share your tips for keeping pond water clear naturally, and backyard pond algae control in the comments below.

How To Naturally Clear Pond Water Without Harming Fish