How to Keep Pond Water Clear

No one likes to have a pond that is not clean.  It will deteriorate the look of your home, it can harm any aquatic life, and if it is used for swimming, no one will want to swim in there.  

It would not be healthy.  It is not hard to keep pond water clean and in this article, it will show you how to accomplish this.

Why Pond Water may not be Clean

There are a variety of reasons that your pond water may not be clean.  If your pond is near pine or other trees, the leaves and needles may have fallen into the water and are just allowed to stay there.  Over time, they start to release tannins, which turn the pond water to an unappetizing shade of brown.  It could also be due to wet debris that has broken down and forms a mixture of sediment on the bottom of the pond.  If you have fish in the pond, with them swimming around can stir up the sediment.  There could also be the problem of algae, which can cause your pond water to go from a light green to thick mucus-like mats.  

How to Keep Your Pond Water Clean

1. Do not overfeed your fish

When a person feeds fish many tend to overfeed them.  What they do not eat will be left to decay in the water.  You should not feed them more than once a day.  Give them no more than what they will eat in two to three minutes.  When looking for fish food, choose one that is good quality and will float on the water instead of sinking to the bottom.  In the winter and autumn, you should reduce the amount of food you feed them because during this time their metabolism slows down.

2. Have a healthy fish population

You should know approximately how many gallons of water is in your pond.  The reason is that you should not have more than 10” of fish for every 100 gallons of water in the pond.  If there is excessive fish waste, it can cause an imbalance in the pond water.  

  House & Indoor Plants Temperature Guide

3. Pump – right size

The pond water should be circulating the complete pond’s water volume a minute once an hour. Check to make sure that the flow is not restricted by debris in the biological filter or skimmer.  Do not pump the water higher than what it was intended as each pump has its limitations.  

4. A proper balance of plants

At the peak season you should have 40-60% of the surface of your pond shaded or covered by various plants.  If you have too many of them, it could cause oxygen deficiencies at night because of the photosynthetic process.  This is when the plants take in oxygen and give off carbon dioxide.  The oxygen is what your fish need to survive in your pond.

5. Proper filtration

The filter should also match the size of your water garden, just like the pump.  Most of these filters are based on ideal circumstances and if you should go over them then the filter is not as effective.  Size up your filter to make sure that it can handle more than what you need.  Keep your filter clean according to the instructions.  Most will require that you clean them once a week.  This includes removing the filter, spray it down with a hose, and then replacing it.  If it starts to struggle noisily or starts to leak, it may be time to clean it.  Some filters have a gauge on it that will let you know when to clean it, which is when the back-pressure reaches four to five pounds.

There are two types of filters you can get.  One is called a skimmer, which is a mechanical filter.  It just removes the surface debris like small sticks and leaves.  The other type is a biological filter.  It is positioned to create the beginning of a waterfall in your pond.  This is the type of filter that uses bacteria to break down the wastes found in the pond and converting them into a less harmful compound.  It can be absorbed as fertilizer by the plants.

  Wandering Jew (Tradescantia Genus) Care & Growing Guide


pond water

6. Clean debris from the pond

Most of the debris will be removed by the pond’s filter system.  When you have decaying debris it mixes with the fish waste and can cause the ammonia levels to spike.  This can be harmful to the fish. If you see the fish jumping out of the water, the ammonia level might be high.  You should buy an ammonia kit at the pet store.  If the levels are high, treat your pond with an ammonia neutralizer.  It will help to keep your pond water clean and healthy for the fish.  By treating your pond, it will break down the debris and help to maintain the right nitrogen level so the fish can get the oxygen they need.

Some will use a pond vacuum to clean the bottom of the pond.  It is designed to suck up sludge, leaves, algae, and other debris from the bottom off the pond.  

7. Keep it cool during the hot summer days

When the water in your pond goes above 75 degrees Fahrenheit, it will have a difficult time retaining levels of dissolved oxygen that are acceptable.  This is why it is important to keep the surface of the water shaded with aquatic plants.  Fish need oxygen to survive so if you see them at the surface of the water appearing to gasp for air, you can add an aerator to help in times of extreme heat.


Most ponds are man-made and should be a place that creates a healthy environment for the plants and fish there.  It also adds value to your home.  It is the job of everyone that has a pond to keep it clean for the fish that live there. Although it is man-made, it is still part of nature so it needs to be kept clean.  When you keep your pond water clean, it makes for an inviting place for people to go to relax and enjoy nature.

Keep reading: How to Grow Amaryllis in Water