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How do I clear my green pond water?

You want crystal clear pond water. Doesn't everyone? At Cool Ponds, we're experts at building ponds that people enjoy, and that means creating ponds that are easy to take care of and remain clear-- always! Read on to learn how we keep our pond water clear.

crystal clear pond water

Not all ponds are alike! Your climate, your tap water, your fish load, the frequency you clean your pond, your pond's history, and more -- all of it make your pond totally unique. Anyone who tells you they have a magic bullet for your green water ailments is lying and potentially selling you something unsafe.

It cannot be stressed enough that if you can come to our support center, please do so! Bring a water sample and some photos, and we can diagnose your pond issues and recommend the right course of action for your pond-- after all there is no one-size-fits-all solution. 

5 Steps to Clear
Green Pond Water

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Step 1.  Determine why the water is not clear

How you will clear your water is determined by what is causing it to not be clear. The Debris vs Algae photo shows that it is difficult to determine the cause by just looking at the pond -- they look similar. But once you take a sample of the water the difference becomes clear. 

Do you have a single cell algae bloom like the right side of the photo? Then continue to step 2. If you have a debris issue like the left side of the photo, click the button below for advice.

pond treatments for algae

Step 2.  Add Beneficial Bacteria

Although beneficial bacteria grows naturally in all bodies of water, in our backyard ponds it needs to be supplemented to keep the water clear. Beneficial bacteria works by breaking down nutrients in the pond and also competes with single celled algae for food essentially starving it.

Not all beneficial bacteria products in the market are the same. Our Cool Ponds BioClear and Clean is highly efficient and effective at keeping water clear. For existing green water situation, we recommend our Cool Ponds BioClear EXTREME, a live bacteria which makes it faster acting. 

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Step 3.  Aerate your pond.

Although having a waterfall or a fountain is important for circulation, it doesn't count for aeration. An aerator pushes oxygen from outside the pond to the bottom of the pond. Beneficial bacteria is aerobic which means is needs oxygen to thrive and multiply. Adding an aerator ensures the entire water column is aerated not just where the water breaks the surface which you have with a waterfall or fountain.  (As a bonus, they're great for deicing in the winter!)

pond plants fight green water

Step 4.  Use the right aquatic plants.

To battle algae, you need to starve it. The right aquatic plants will compete directly with algae for nutrients. In our experience, marginal plants (or shallow water plants) are the best long-term solution for competing with algae. Make sure you have plenty of them!

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Step 5.  Be Careful With Fish

There is nothing better than watching our fish cruise around our pond! And fish aren't the problem... we humans are. Our issues with fish cause so many green water problems! First off, don't let your pond get overpopulated with fish. Second, don't overfeed your fish. Third, make sure you are using only high protein fish food. Fish waste = nutrients in your pond = algae!

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Bonus: Add River Rock to Your Pond

So we have already mentioned beneficial bacteria in steps 2 and 3, let's talk about it some more. Beneficial bacteria grows on all the surfaces under the water in your pond. By adding a 1" to 2" layer of river rock to the bottom of your pond, you are increasing your surface area for beneficial bacterial exponentially! 

Grab Our Clear Water Checklist

There's more to this story... Actually there are many other steps you can take to ensure you have clear water. We've made navigating the path to clear pond water easier for you with our clear water checklist. 


Click the image above to open the PDF in your web browser.

Get Our Treatment Regimen

It can be confusing knowing what water treatments to use and when and how much and how often... So we've cleared that up for you! 

We have a schedule and dosage chart in a convenient PDF for you to download. Hang in on the fridge, keep it in your treatment tote -- and remember to use it!

Cool Ponds Treatment Regimen.jpg

Click the image above to open the PDF in your web browser.

If you have more questions, we have more answers.

how to oxygenate your backyard pond
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