Are you searching for how to maintain a pond with fish?
If you ask a dozen water garden owners why they built a garden pond in their backyard, you’ll end up with a dozen answers. People add water features to their yard for a myriad of reasons: adding aesthetic value to property, drowning out street noise, or they simply have a love of water. No matter the reason there are some basic tips to keep a garden fish pond looking its best.
However, pond maintenance doesn’t have to be time-consuming, or highly technical. If you keep in mind these routine things to do you’ll keep your pond water clean and the fish that live in it, happy.
How To Maintain A Pond With Fish – 6 Essential Tips
Test water weekly
One of the most important aspects of having a fish pond is keeping the chemical levels of the water in the appropriate ranges. Waste from the fish (occurring as ammonia) will progress naturally through the nitrogen cycle within the water. Naturally occurring bacteria called nitrosomonas convert the ammonia to nitrite; and nitrite is broken down by a second type of bacteria called nitrobacter into nitrate. While it’s okay for nitrates to occur in the water at a small level, ammonia and nitrite can be toxic to fish and plants so it’s imperative the nitrogen cycle works efficiently.
A pond test kit will help make sure levels are within appropriate ranges. Ideally ammonia and nitrite shouldn’t be found in any discernible levels, and nitrate should be kept between 20 – 50 ppm. Nitrates will be consumed by plants within the pond, and only become dangerous to fish when the nitrate level exceeds 150ppm. The pH of the water should be monitored too and ideally maintained between 7.0 and 8.0.
Filter the water
A good filtration system serves two purposes in a fish pond: filtering debris from the water, and aiding in the pond’s biological processes. Fish produce ammonia waste and the nitrogen cycle begins. Biological filters give the good types of bacteria a concentrated place to live. At the same time drawing water through biofilters bombards the bacteria with a constant source of ammonia and nitrite in the water. Biofilters also provide oxygen to the bacteria, a key component in the conversion of ammonia and nitrite.
A good filter system should be the highest priority budget item when looking to install a fish pond. When designing a filtration system, it’s best to implement both mechanical and biologic filters. This will provide the best results as long as they are sufficient in size to match the pond volume. Keep in mind that it isn’t possible to over filter water, but water that isn’t filtered correctly will quickly encourage algae growth and could harm fish if ammonia and nitrite levels spike.
Add rooted plants
Installing aquatic rooted plants in a fish pond has many benefits to the pond ecosystem. Plants feed on nitrates found in the water, the end result of the nitrogen cycle, which occurs to breakdown fish waste and other organic matter. When nitrate levels reach a certain threshold it encourages algal growth and can become detrimental to fish.
Rooted plants will help to keep nitrate levels in check and in turn, slow algae growth. When absorbing nitrates through the roots, plants also take in phosphate and some metals, reducing the quantity of these nutrients/minerals as well. They also provide shade which helps prevent algae growth and they add oxygen back into the water through their respiratory process.
Remove debris as needed
An open expanse like a pond is going to collect items such as grass, leaves, and other large debris. It’s important to remove these items quickly before they have the chance to settle to the bottom of the pond. Once they settle they not only are more difficult to remove but can also lead to algae growth and a spike in ammonia levels as they begin to decompose. A simple pond skimming net will make quick work of this step and keep the water looking much cleaner.
Top off water as needed
The water level in your fish pond will gradually drop over time. This may be due to evaporation, or simply splashing out from fountains or other water features. In really hot, dry conditions it’s not unusual for a pond to lose ½ – ¾” of water per day.
To keep from altering chemical levels too widely it’s important that water is added in small, more frequent amounts to keep levels stabilized and the water level appropriately high for the filter(s) and pump. Add no more than 30% of the pond’s volume in new water to the pond at any given time, making sure to treat municipal water before adding it to remove any chlorine and chloramine introduced in the treatment processes. These chemicals are very dangerous to pond fish.
Clean liner once a year
Over time you’re going to get some algae and sludge that builds up on the pond liner at the bottom. To keep your fish healthy and the pond looking its best you should give the liner a good scrubbing at least once a year. Many gardeners choose to do this in the spring, after the pond freezes for the winter and the fish are slowly acclimatizing as the water temperature climbs. This also means the season starts off with a pristine clean liner.
Pump the water out into a large tub or containers until the level is just above the fish. Then move the fish carefully into the container with the water that was pumped out. Continue pumping the remaining water to access the liner. Use a large dust pan and broom to remove the sludge from the bottom, being careful to not scrub the beneficial velvet algae that coat the liner.
When the liner is clean, start pumping the old water back into the pond, returning the fish. Top off the water as needed treating it for chlorine.
Keeping a fish pond thriving and healthy requires some maintenance, yes, but a little work will keep the water clean and the fish happy. The whole process will run much more smoothly if the above steps are followed!
Please share with us your experience, what have you found to be effective on how to maintain a pond with fish?