You've decided to give your outdoor pond a facelift and you're looking for cleaner fish to keep the environment clean and healthy. Perfect, you've come to the right place! Now, let's be honest, between choosing the species and managing the technical equipment, it's easy to feel overwhelmed. Don't panic, let me guide you through some practical tips, tested and approved by a bunch of happy fish in my own pond.
Choosing the right fish species for your pond
The choice of fish species is vital. A number of parameters need to be taken into account to ensure the survival and well-being of our aquatic friends.
Pool volume and depth
The size of the pond is one of the most important aspects. A small tank will quickly fill up with debris if you introduce too many fish. Goldfish need at least 500 litres for a group, whereas Koi carp require a minimum volume of 1,000 litres per fish. Don't forget that large species such as the Sterlet sturgeon require an even greater volume, up to 10,000 litres.
The depth of the pond also plays a key role. Fish need to vary their depth according to the temperature of the water. In winter, they take refuge in deeper areas to avoid the cold. A depth of at least 1 metre is recommended for Koi, while certain species such as Gambusia can be satisfied with shallower ponds.
Influential technical equipment
Filtration and aeration are essential for maintaining water quality. Modern filtration systems not only remove solid waste, but also help to break down nitrogen compounds. Aeration keeps the water oxygenated, which is vital for fish health. Regular maintenance, including partial water changes, will prevent disease and ensure optimum living conditions for your cleaner fish.
| Species | Min. pool volume | Min. depth |
|---|---|---|
| Goldfish | 500 litres | 50 cm |
| Koi Carp | 1,000 litres | 1 metre |
| Sterlet sturgeon | 10,000 litres | 1.5 metres |
| Gambusia | 50 litres | 30 cm |
Maintaining pond fish: water, food, diseases
Once the fish have settled in, maintaining the pond becomes your main concern.
Maintaining water quality
Water quality is essential. Clear, well-oxygenated water improves the health of your fish. Use oxygenating plants and accessories such as fountains or water jets to promote oxygenation. Avoid silt by using maintenance bacteria and silt vacuums.
Feeding fish
As far as food is concerned, each species has its own needs. For example, grass carp is phytophagous and could devour all your aquatic plants. It is vital to provide the right diet for each type of fish, while avoiding over-nutrition, which can lead to an accumulation of organic waste.
Preventing and treating disease
Diseases among pond fish can be bacterial, fungal or parasitic. To minimise the risks, maintain UV filtration to reduce pathogens and ensure that the water remains of high quality. If a fish becomes ill, consider isolating it in a 'hospital tank' for any necessary treatment.
What are filamentous algae? How do you get rid of them?
Ah, the algae These undesirables can quickly turn your pond into an unattractive green soup.
Dangers of filamentous algae
Filamentous algae often appear due to an excess of nitrates and phosphates in the water. They are dangerous because they can depleting the water of oxygen and compete with other plants and fish for resources. They also reduce the space available in the pond.
Solutions for controlling algae
There are several solutions for controlling these algae:
- Plant oxygenating plants
- Installing efficient filtration systems
- Using accessories as stunts
- Monitoring the fish population
Certain species of fish, such as herbivorous carp, can also help by eating the algae. However, it is important to manage the biological balance of the pond to avoid excessive proliferation of these undesirable algae.
These tips may be of interest to you
Finally, here are some other tips you might find useful for maintaining your pond.
- Measure the volume of water available for the fish: Use a measuring tape to calculate the length, width and depth of the pond.
- Use of appropriate filtration systems: Pressure filters, gravity filters and drum filters are some of the options to consider, depending on the size of your pond and fish population.
- Combating silt: Use specific techniques to suck up silt and avoid it on a regular basis.
- Various factors influencing water quality: Monitor parameters such as pH, water hardness and oxygen levels.
To finish on a more personal note, let me share an amusing anecdote from my life as a pond lover. Once upon a time, I had a goldfish called Albert, who was an expert at escaping. One day, I forgot to put the safety grate back on after maintenance... you can imagine my surprise when I found him in my vegetable garden the next morning! Since then, Albert has had a VIP place in an escape tank. Ah, the joys of being an aquarist!
Dear readers, what adventures have you had with your aquatic friends?
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