Most pond owners know the importance of good water quality in a pond’s ecosystem. New pond owners may not be aware of these requirements initially, but there is still time to learn what your water garden needs to keep clean and healthy.

The first thing to realize is that the water is not what’s green in color. Millions of single-celled algae swim in the water, and that’s what you’re seeing. Algae isn’t particularly harmful on its own. 

Unless your fish develops to extraordinary sizes, it normally won’t harm them. It’s only there because it’s how nature handles extra nutrients. At least little algae can and should be present in every pond. So, here are some expert methods for achieving and maintaining clean pond water.

Maintaining a healthy fish population is essential

Ensure that your pond isn’t overcrowded. The guideline is that for every 100 gallons of water, no more than 10 inches of fish should be present. Disproportionate volumes of fish feces might cause an imbalance in your pond’s water quality. Consider finding them a new home if you have too many fish.

On the other hand, the size and efficiency of your filtration system affect the number of fish you may maintain in your pond. If you’re having trouble keeping your water clean or seeing a lot of string algae, it might be a sign that your filtration system isn’t up to handle debris, fish waste, and supplying enough oxygen.

Establish a good plant balance

Plants should cover or shade 40 to 60% of the surface area of your pond in the ideal situation. The photosynthetic process, in which plants take in oxygen and release carbon dioxide, can result in oxygen deficiency at night if there are too many plants. 

Your fish will die if they don’t have enough oxygen. These plants also serve as natural filters, flourishing on surplus nutrients that would otherwise cause algae to proliferate. Keep any leaves or other debris out of your water regularly to prevent it from rotting and flooding your pond with ammonia.

Don’t give your fish too much food

Keep note of how much food your fish can consume in a 2- to 3-minute period. After that, all of the leftover food sinks to the bottom of the pond and decays, so don’t feed them more than once a day.

Koi and goldfish, for example, can mostly thrive on mosquitos and other pests that would otherwise take over your water feature. When adding flakes or pellets to your fish’s food, feed as much as they consume in a few minutes.

Overfeeding your fish won’t make them fat, but it will ruin your pond. Chemicals will contaminate your water and potentially destroy your pond life.

Purchase a high-quality pump

You should circulate the whole pond’s water volume at least once an hour. Make sure your pump’s flow isn’t obstructed by dirt in the skimmer or biological filter, and don’t push water higher than it was designed to go. Every pump has a set of flow restrictions. Examine the chart on the back of the pump’s box to ensure you buy the correct pump for your pond.

Remove any debris from your pond

Your pond skimmer will remove most of the waste from the pond’s top, but you may also use a pond net to skim leaves and tiny sticks before they reach the pond’s bottom, where they will decay.

Decaying detritus, feces, and uneaten fish food gather rapidly in your pond. To avoid an increase in your water’s ammonia levels, make sure you clean out your pond regularly. Beneficial microbes, such as Aquascape’s Beneficial Bacteria, assist in maintaining a healthy environment in your pond.

Set up the right filtration system

Choose a filter that is appropriate for the size of your pond. It’s worth noting that most manufacturers rank their filters under ideal conditions. If you go over certain limits, your filter will become less effective.

You should always scale up your filter to take more than your pond’s capacity. Remember that you must clean your filter according to the manufacturer’s directions.

In an ecological pond, there are two types of filters. A motorized filter, often known as a skimmer, removes residues such as leaves and tiny sticks off the surface of your pond.

The biological filter, the BioFalls filter, is placed in your pond to start the cascade. This filter employs microorganisms to break down pond trash, transforming it into less toxic substances that your aquatic plants may absorb as fertilizer.

Aquascape 9020 Signature Series 2500 Pond BioFalls Filter, Black
  • Provides effective biological and mechanical filtration for ponds up to 2,500 gallons
  • Durable, rotationally-molded polyethylene construction and rounded shape maximizes structural strength
  • Includes everything needed for simple and easy installation

During the summer, keep your pond cool.

When pond water reaches temperatures above 75 degrees Fahrenheit, it has a hard time holding sufficient quantities of dissolved oxygen, which is essential for your fish’s health. 

During high heat, you may notice your fish gasping for air at the pond’s surface, which aquatic plants assist in preventing by providing shade and cooling the water’s top. In those scorching conditions, adding an aerator helps them get the oxygen they need.

Maintain all of your pond’s equipment properly

A good filtration system, a robust pump, a protein skimmer, and an aeration system are usually included in this setup. The pond pump is used to pump water into and out of the pond, which helps to keep the water moving properly.

When used in conjunction with the protein skimmer, the filtration system is extremely effective at keeping the surface water clean. A floating de-icer, as previously noted, can help maintain appropriate gas exchange in the pond throughout the winter.


Is a filter required for my pond?

Yes, having a filter in your pond is useful since it is the greatest method to maintain it clean, reduce ammonia and nitrate levels, and guarantee that the water is adequately oxygenated.

How often should the water in your pond be changed?

If you’re having problems with ammonia or other water quality issues, you might want to increase the proportion or frequency. We recommend changing 10-15% of the water in smaller ponds, such as those under 5000 gallons, once a week. For larger ponds above 5000 gallons, a weekly water change of 5-10% will suffice.

Is it possible to clean pond water?

Barley straw, weird as it may sound, is the answer to natural pond algae management. Barley straw is not just a natural pond algae killer but also safe for your fish and plants.

Final thoughts

A fish pond may be a stunning feature in your yard, bringing delight to everyone who comes to see it. You won’t have any trouble keeping your pond water clean if you remember and use all the suggestions and tactics described above. Best of luck!

Last update on 2022-09-11 / Affiliate links / Images from Amazon Product Advertising API