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.
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…
Table of Contents
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!
Recommended Reading
- Backyard Water Gardens
- The Water Gardener’s Bible
- Water Garden Idea Book
- Encyclopedia of Water Garden Plants
Products I Recommend
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.
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.
Patt says
I use Barley straw as well. I do like it. I use it in 3 ponds. But I put one in, in the spring, then another one in the middle of the summer. But I do recomment it. I make sacks for the straw and put the straw in it.
Amy Andrychowicz says
Awesome, thanks for sharing your experience with using barley straw to get rid of pond algae. Glad to hear it works well for you too! 🙂
Diane says
My new pond was starting to get murky. I used the barley straw; in just 2 days the water was clear right to the bottom. I don’t know why some ponds don’t respond well to the barley but mine was a few day clear method.
The bale has just now absorbed enough water to sink and I’ll watch to see if there are any changes.
I have a 500 gallon tank, 4 ft deep, built above ground, 3-tiered fountain, nine Koi and 30 algae eating snails.
My Koi are happy and fun to watch as they “frolic” throughout the pond. I have many “hide-y” holes for them to swim around and through.
I’m most pleased with the pond and it requires little work other than cleaning the pump every couple of weeks.
I am going to use a tank water heater regulated just to keep the water from freezing and possibly keep my waterfall in use year round.
I hear that many people remove the pumps for the winter.
Amy Andrychowicz says
Awesome, so happy to hear that barley straw worked so fast to clear your pond! Woohoo! It gets very cold here in MN, so I have to use a pond heater to keep mine from freezing over, and I must turn off the waterfall. I don’t remove my pump though, since the heater keeps my pond from freezing to the bottom. Here’s a post I wrote all about how to winterize a pond.
Brenda says
Hi, I have a very large pond with a 4 Ft waterfall. I don’t remove my pump in the winter and I don’t have a heater either, I just run two bubblers in the pond it’s self, so my fish have two air holes for oxygen and pond gases to escape. I have only had it for one winter and all but’s two fish did well, but they were from a pet store. I shut the waterfall off in the winter and only run the bubblers in the lower pond.
Joanne Lebo says
My husband and I have a quarter acre pond with a stream running through it. We tried to keep it clean manually, but we couldn’t keep up with it because of separate health issues. Our pond has about 100 koi and several types of frogs that live in it. I am sure there are other sweet critters as well. Our issue is that the pond has a lot of overgrowth and it smells so horrible I could almost gag. Where would I get a free test kit to see what problem needs addressed exactly? I have ordered a few hundred dollars worth of different pond cleaning stuff and it will be delivered this weekend. We just don’t know which way to turn at this point. All the things I’ve ordered claim to be safe for pond life.
Amy Andrychowicz says
Oh bummer, so sorry to hear you’ve been struggling with stinky and mucky pond water! I’m not sure where you could a free test kit, but they’re not very expensive to buy. Here’s the one I have… pond test kit.
June says
You need oxygen in your water. We had the problem of stinky water. Added a windmill, attached to it was a hose and a air pump. Put a weight on the hose with the air pump and sunk it in the deepest part of the pond. The windmill catches the wind and turns the blades on the fan, that pumps air down through the hose in the bottom of the pond and releases oxygen. You see the air bubbles on the top of the water. We also added a floating electric fountain. This aerates the surface water. Purchased pond muck cleaner. It also helps if you can get rain water to flow into the pond. We have a 4 foot ditch that surrounds the pond and put a pipe that connects the ditch to the pond. When it rains heavily the ditch water flows into the pond. All of this has helped tremendously. No more stinky pond. We have stocked it and it is beautiful.
Art D says
Another tip for filtration, apparently activated charcoal is this:
Make a fire using Hardwoods. Once all of the wood have become Red Hot Cherry Coal feed your fire water, as much as it takes to subdue the coal.
Now the charcoal has become activated. Break into whatever size pieces you need and thoroughly rinse.
Note, it will smell like a campfire when rinsing but that will quickly pass. I’ve done this myself and find it’s a lot cheaper than buying already activated charcoal at the store. I haven’t yet tested it for drinking water, but that’s on the do.
Amy Andrychowicz says
Great, thanks for sharing your method of clearing pond water! I like the charcoal idea.