Perfect water quality and improved operating efficiency with the spacesaving Defender® regenerative media filter
Bremer Bäder GmbH operates many leisure, indoor and outdoor swimming pools in Bremen. Every year, over 1.7 million guests enjoy the wide range of activities on offer, which include sports, as well as wellness and relaxation classes, and swimming fun for the whole family. To continue meeting visitors’ needs in the future, the operator is continuously investing in the modernization and expansion of its facilities.
The challenge
The outdated open media filters at the Blumenthal outdoor pool, operated by Bremer Bäder GmbH, were prone to malfunction, which frequently disrupted normal operations and resulted in considerable repair costs.
Since the principle of media filtration and the resulting excellent water quality have proven effective over decades, it has been decided to retain it. In any case, the installation of a sand filter system in accordance with DIN 19643 was not possible due to limited space. However, to increase efficiency, the time required for cleaning and new silting of the open filters needed to be significantly reduced.
These technical challenges made urgent improvements to the filter technology necessary.
The solution
Bremer Bäder GmbH has relied on Wallace & Tiernan technology from Xylem for many years. As a result of this, advanced technology from Neptune Benson, also a Xylem brand, was selected for the filtration of the swimming pool water. This decision reflects Bremer Bäder GmbH’s commitment to ensuring the highest standards in water treatment and providing guests with a safe and enjoyable swimming experience.
Regenerative media filters are an efficient alternative to sand or multi-layer filters. They significantly reduce flushing water consumption. In addition, they only require about a quarter of the installation space of conventional filter systems. In most cases, they also consume less energy and lead to savings in chemical use (e.g. elimination of flocculants).
For these reasons, the Defender® regenerative media filter was installed at the Blumenthal outdoor swimming pool. It impresses with its high performance, durability, and user-friendliness, contributing to the sustainable operation of the outdoor swimming pool.
The results
The replacement of the open media filters was successfully carried out between autumn 2024 and spring 2025. Since then, two Defender systems have ensured reliable filtering operation without any failures. Thanks to the timely conversion to the new filter system, the Blumenthal outdoor pool was able to start its season on time.
All parties involved – Bremer Bäder GmbH as the operator, the engineering firm Wolff + Partner as the planner from Bremen, and Blume Schwimmbadanlagenbau from Osterwiek – have contributed significantly to the success of this project. The result fully meets all the requirements set for the new system.