Pond

filter

Choosing the right pond filter system

Before ordering our pond filters from our online shop, please take the time to read this information. Below, we would like to give you a brief insight into the necessity and functioning of a filter system.

The two stages in the pond filter system

We always distinguish between two different types of filtration in a pond filter system. The first stage is the removal of undissolved dirt particles from the water. This involves removing leaves, algae, faeces, food residues, etc. from the water. A pond filter can ensure that coarse contaminants are reliably removed and the water remains clear. 

The second stage is the so-called biological stage. This involves the breakdown of dissolved substances in the water. In the biological stage of a pond filter, substances that are toxic to fish, such as ammonium and nitrite, are converted into substances that are non-toxic to fish, such as nitrate, with the help of bacteria. Without an effective pond filter, the water quality could deteriorate and the ecosystem in the pond could become unbalanced. 

The removal of solids from the water by a pond filter is easy to understand. It becomes more complicated when it comes to removing dissolved substances, as these cannot be seen with the naked eye. This raises the question of how these substances get into the water. Everything that lives dies at some point – that is the normal cycle of life. Dead plants, fish faeces and food residues are organic compounds that are broken down by microorganisms. This decomposition produces substances that are toxic to fish, such as ammonium. A high-quality pond filter can ensure that these substances are effectively removed from the water or converted into harmless substances, so that the pond remains healthy in the long term.

Nitrification in the biological pond filter

A good biological pond filter breaks down these toxins dissolved in the water immediately. This breakdown occurs with the help of oxygen and microorganisms, known as Nitrosomas and Nitrobacter bacteria. These bacterial strains convert ammonium into nitrite and then the nitrite into nitrate, which is toxic to fish. This process is known in technical terms as nitrification. 

In order to achieve fast and effective nitrification in the pond filter, it is essential to only feed pre-cleaned water into the biological stage of the pond filter. This means that the water must be free of all suspended solids and solid particles. If you feed a lot of dirt particles into the biological stage of your pond filter, it will become clogged and its function will be massively reduced. A powerful pond filter can ensure that the water is optimally treated and that the biological filtration works reliably. 

A pond without a properly designed pond filter is like a house without a toilet. Sooner or later, you will encounter significant problems with this system. These problems begin with diseases in the pond's inhabitants and, in the worst case, can lead to the death of the entire ecosystem. This is known as the pond "tipping over" – a condition in which all koi and other creatures die at once. A high-quality pond filter can prevent this problem and ensure stable water quality. 

We have given a lot of thought to the range of filters on offer and rely solely on our own experience when providing information about pond filters. Our recommendations for pond size and pump power often differ greatly from the manufacturer's specifications. However, it is important to us to offer a pond filter system that works perfectly and is specially designed for koi ponds.

Determine the exact pond size for the right pond filter system

In order to make a reliable statement about the size of the pond filter for your pond, you absolutely need to know the exact volume of water in your pond. By exact, we really mean exact, not approximate figures such as "roughly", "could be about right" or "I guess". Check your own estimate with a simple calculation formula. 

My pond has a volume of approx. 20 m³ (according to our enquiry, it was 5x4 m wide). Upon further enquiry, it turned out that it was almost 1.50 m deep throughout, which according to our calculation results in 30 m³. We don't mean to sound pedantic, but we have conversations like this every day. Such inaccurate information always works to the detriment of your own pond, as you will ultimately have to live with a pond filter system that is too small. An exact water volume is also crucial when it comes to pond filter care products or parasite control. Even the best product will not work if the dosage is incorrect. 

When choosing your pond filter, keep in mind that there is no such thing as a pond filter system that is too large, but there are many systems that are too small. A pond filter that is too small results in high follow-up costs, additional work and can lead to significant problems in the pond in the long term. A powerful pond filter, on the other hand, ensures stable water quality and significantly reduces maintenance.