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!
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.
In this guide, I’ll give you all the details of how to clear pond water, and keep it clear safely, without harming your fish or plants!
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!
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!
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!
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.
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.
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!?
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.
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.
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.
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.
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.
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
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!
Recommended Reading
- Backyard Water Gardens
- The Water Gardener’s Bible
- Water Garden Idea Book
- Encyclopedia of Water Garden Plants
More Gardening Techniques
- Growing Vertically: The Ultimate Vertical Garden Guide
- Plant Propagation: A Detailed Guide For Beginners
- How To Build A Rain Garden Step-By-Step
Share your tips for keeping pond water clear naturally, and backyard pond algae control in the comments below.
ALAN FISHER says
imo ,you should not wash /rinse the filter media[sponge] with hose or tapwater as it kills the good bacteria use rain water, or declorinated water , even a bucket of pondwater .. .
Treena says
Hi I have a large natural spring pond which my horses drink from,I’ve had string weed in there but when I brush some back I’ve been finding lots of black beets with red fins.. how can I clear without disturbing these?
Many thanks thanks
Amy Andrychowicz says
The remedies we recommend in this article for clearing pond water are all natural and will not harm any bugs or other organisms in the water.
stuart says
what do you suggest for a 0.75 acre pond are these methods still viable?
Amy Andrychowicz says
Yes, these methods will work for clearing the water in any size pond.
Mark says
I have a 5000 gallon pond and want to get rid of the moss in it. The pond waters grape vines that I don’t want to harm. Will your product work?
Amy Andrychowicz says
Yes, the methods I recommend in this article for clearing pond water are all natural and won’t harm your plants or fish.
Charlene says
My grandchildren threw dirt in my pond. I need a tight skimmer to remove it. Is this available?
Amy Andrychowicz says
Yes, you definitely should be able to find a pond skimmer that has a tighter mesh that will help you remove at least some of the dirt from the bottom of your pond. You could also use a pond vacuum, which is expensive to purchase, but you may be able to rent one.
Bridgette Ranck says
Hi Amy. I have a small 100 gallon pond with waterfall that I set up this summer and this post has been a lifesaver! I was wondering if you have a book out that can be purchased about this.
Amy Andrychowicz says
Yay, so happy to hear this tutorial has been a lifesaver for you and your pond water! 🙂 I do not have a book on the subject, but thanks for asking!
Micheal CaseyBeich says
Can I use excess pond water that has been treated with a barley bail to water my edible vegetable garden?
Amy Andrychowicz says
Yes, pond water is great for your garden!
Nadine says
I have a very small pond, 35 gallons. There are plates and a few goldfish. The water is green and cloudy. I also don’t have any filter on this pond. I added a canna plant, a dwarf papyrus and some other plant but the water doesn’t seem to be getting better. What do you suggest? Will the barley hay help with the pond set up I have? Thank you for your help.
Amy Andrychowicz says
While the barley straw will kill the algae in your pond water, adding a pump will definitely help to clear it faster, and make it easier for you manage it long term.
terry says
So if I drain and clean the pond do I need to add something in the water for the chlorine? Also I am unable to see the fish since it is so murky. They are small and also have some gold fish. We are not feeding them at all. This is the first summer for the pond. I dug it last fall. The goldfish made it through the winter and we could see them for a while this spring but the water kept getting worse and worse.
Amy Andrychowicz says
Let the water sit for at least 24 hours so the chlorine can evaporate. Remember that it can take some time for the barley straw to work. So try adding some hydrogen peroxide like I mentioned in the post. That can help speed things up.
terry says
I have a 2000 gallon pond with a stream. It has 24 fish in it which I can’t see because the water is so murky. I have used charcoal…barley straw…another pump covered in batting…and now am on my 3rd week of beneficial bacteria…nothing is working. It seems to get worse. I really dont know what the next step is except perhaps drain it which I really would rather not. Anymore suggestions?
Amy Andrychowicz says
I would definitely recommend cleaning your pond, and also testing the water to see if there’s some imbalance that needs to be corrected. The remedies you mentioned for clearing pond water do take some time to work. So keep that in mind too. Also, you mentioned that you have 24 fish in the pond, which might be too much, depending on how large they are. If they are very large koi, then you may need to relocate a few of them. The rule of thumb is about one 6″ fish for every hundred gallons of water. Oh, and make sure you’re not overfeeding them. All that excess food can make it harder to clear the water.
Chris A says
I would suggest adding a UV filter or 2 (considering the size) I believe I seen 1 in Amazon $150. My pond is only 900 gallons and I installed one and see. A difference in about 4 hours. After installing clean daily for a week. Once you have it under control you can reduce to 2-3 times a week.
Daniel Waligurski says
Cured my green water by building a pergola. I built a 10×20 over the pond with a porous cover. Also a plastic barrel used with rock and filters. It kept my 3000 gal. pond crystal clear all summer.
Amy Andrychowicz says
Wow, sounds great! Thanks for sharing your tips for how you cleared your green pond water.
Melody says
Must it be Barley bails or can I make my own bundles out of cow hay?
Can barley bails be cleaned and reused?
Thanks
Amy Andrychowicz says
No, regular hay won’t work. It must be barley straw. The barley straw will rot in the pond, and as it does, it will release the chemical that clears the water. You can’t reuse the bundles, because the straw will rot away. 🙂
Sue Ising says
I have a 9000 gal pond used to be crystal clear now green and murky i need help dont’ want to keep buying chemicals we put in a gravel filter this summer so it is helping some…..
Amy Andrychowicz says
With such a large pond, tossing in a barley straw bundle or two every spring might be your best bet. It will take some time for the filter to clean the water, so the fact that you’re already noticing a difference means you’re on the right track. Good luck!
Pat says
Bought barley straw now what do I use to make a smaller bag to hold the straw. .?
Amy Andrychowicz says
I used the mesh bag that my barley straw came in. I just cut it in half, which ended up being the perfect size for my small pond. The mesh bags that some types of produce comes in work great too. You could also buy a mesh material at a fabric store, like tulle or something similar to that, to use to make a small bag for it.
PReed says
I bought a mesh bag at a dollar store. They are usually in the washing section, use for washing delicate fabrics in the washing machine.
Patt says
I went to the fabric store. then I got material that looks much like gunny sack so that water will get into it. I made 6 bags and stuffed them with the straw. That will be enough for the summer. But the material looks much like that old doily stuff.
Nadene Sanderson says
Will adding bleach to a pond work? I have no fish and no plants. I want to see the bottom again.
I do have a waterfall, skimmer, as well. No debris is left in it. But does have full sun
Amy Andrychowicz says
Bleach would probably work to keep your pond water clear, I have never tried it myself. However, that would kill everything in the pond, plants and all – and it wouldn’t really be a true pond anymore. So, I don’t recommend using such a harsh chemical, especially when there are lots of more natural alternatives that work great – and then you would be able to keep fish and plants in your pond.
Patt says
You might want to try Barley straw. I make bags to hold it, and get the fabric at the fabric store. I order the straw from the Amazon. This will help the algea. It will not make for a perfectly clear pond. But using bleach will be pretty harsh. The dogs and birds are harmed with bleach. Feel free to ask me more.
Patt says
It will but birds and other animals drink that water. So not so good.