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The fish pass for an ecological balance

The Fishcon fish pass combines ecological water protection with sustainable use of hydropower. The Fishcon lock, also known as a 2-chamber organism bypass, has a modular structure and can, therefore, be used quickly and cost-effectively.

Low space requirements
For different sized bodies of water
Cost-saving investment
 Energy supply

Modular construction
No noise emissions
Safe migration


Simple structure that convinces

The innovative fish pass consists of two chambers with slide gates to the upstream and downstream water, a pipe bend that connects the chambers and a turbine or throttle device, which is located in the connecting pipe bend and limits the flow. In order to prevent organisms from swimming into the connecting pipe bend, fine screens are arranged on both sides, which automatically clean themselves due to the changing flow.

Due to the rough floor in the chambers, the low flow speeds and the low turbulence, even microorganisms and weak swimmers can safely pass through the fish pass. As a result of the fish migration made possible, the ecological balance in the water is preserved as best as possible – an important requirement of the EU Water Framework Directive.


Protected migration in both directions – with the simple fish pass

The fish pass is a further development of a conventional fish lock. The technology is based on a patented hydraulic interconnection of two lock chambers operated in opposite directions. This mode of operation enables fish to swim in continuously from both sides and prevents the intermittent operation that occurs with conventional fish locks and fish lifts. This leads to an increase in effectiveness and, in addition to the fish ascent, also enables fish to descend at the same time.

The slide gates of the fish pass are always controlled in such a way that one chamber is open to the upper water and the other chamber to the lower water. After a time interval has elapsed, all four gates change their position. Organisms, that have entered the chambers can thus migrate upstream or downstream. To guide the organisms, a conductive attraction flow rate from the upstream water through the connecting pipe bend into the downstream water. The throttle or turbine in the connecting pipe bend limits the flow so that there are optimal flow speeds.


The fish pass for large and small bodies of water

The Fishcon lock is offered in four sizes. If you are interested these will be equipped with turbines for the use of hydropower, that could be interesting due to the high number of full load hours. In the case of very large attraction flow rates or heights, the fish pass is individually adapted to the conditions on site. Combinations with conventional fish passes or several Fishcon locks are also possible in order to overcome large differences in height.


Overview of versions

More construction sizes in progress and several modifications are possible.

The Fishcon lock is currently offered in two standardized designs, with various adjustments being possible. FISHCON will be happy to support you by choosing and planning your Fishcon lock!

DN version
With the DN version, the Fishcon lock is adjusted to the height difference of the site. A large number of adjustments and energetic use of the conducting current doping are possible. The DN version is particularly suitable for large height differences of up to approx. 6 m. The DN version can be operated with slightly higher conducting current doping as standard. By adjusting the slider opening height, however, very small amounts are also possible!

IPE version
The IPE version is narrower and more economical than the DN version. It is particularly suitable for smaller bodies of water and slightly lower height differences of approx. 1 to 4 m. It is not possible to use the conduction current dotation for energy purposes. The pilot current doping can be adjusted within a defined range as standard and natural lighting of the chambers is provided. For installation, the Fishcon sluice is placed on the supplied steel base with adapted angles.


The fish pass has proved itself in tests and has been awarded top marks

Low space requirement

Due to the compact design, only small areas are required for the installation of the Fishcon lock. There are different integration options in order to be able to realize an optimal water connection.

Modular design

The Fishcon lock is delivered to the site as a prefabricated part, which allows for quick and uncomplicated installation. Reliable operation is achieved due to the simple and closed design.

For large and small heights

The Fishcon lock makes it easy to establish water continuity in small and large bodies of water. Irrespective of the size of the body of water, the systems can be operated with very low conductive currents.

Cost-saving investment

Due to the low investment costs and the savings from the energy supply in systems with turbines, the Fishcon lock is a cost-saving solution for creating fish passage.

 Safe migration

The Fishcon lock enables gentle migration in both directions and is suitable for organisms that are weak swimming. The turbine or throttle as well as a rough sole ensure optimal flow speeds.

Resistant execution

The fish pass can be overflowed by the flood. Closing the chambers prevents contamination or dirtying. Furthermore, the Fishcon lock is insensitive to fluctuating water levels.

Reference systems

Discover the reasons behind the top marks awarded to our pilot systems. Gain a better understanding of our reference systems and their strengths.


Find comprehensive answers to the frequently asked questions about our innovative patented 2-chamber organism bypass