Objectives and concept

The CLEANAQ project will develop novel procedures for end-of-pipe nutrient removal to improve the cost-efficiency and to further reduce environmental impact of fish farming in recirculating aquaculture systems in the Baltic area. 

Main goal

The main goal of BONUS CLEANAQ is to produce novel high-quality scientific data, which can be utilized for innovative aquaculture technology, and waste water management.

Objectives of BONUS CLEANAQ

The objectives of BONUS CLEANAQ are:

  • Investigate the applicability of removing nitrate through 
    • single-sludge denitrification
    • carbon-free woodchip denitrification
    • non-microbial nutrient removal methods 
    through end-of-pipe treatment of effluents from recirculating aquaculture systems in the different salinities prevailing in the Baltic Sea area.
  • Find the optimal conditions and the most feasible process design for each method.

  • Find the most cost-efficient and environmentally sustainable end-of-pipe treatment/combination of treatments for concomitant phosphorous removal.

  • Examine the potential to integrate end-of-pipe treatment in recirculating aquaculture systems with energy production.

  • Provide synthesis of scientific results obtained in BONUS CLEANAQ and in other related studies to the industrial end-users and national authorities.


To successfully fulfill the objectives, the BONUS CLEANAQ project will:

  • Use multi-disciplinary research effort by integrating process modelling, novel and existing biotechnologies, advanced equipment and techniques combined with the practical skills, knowledge and innovation expertise of leading operators within recirculating aquaculture systems.

  • Combine mass balances, stoichiometric calculations and modelling with state-of-art stable isotope process measurements and molecular methods.

  • Combine laboratory-scale experimental approaches with pilot-scale setups in real-life RAS environment.

  • Actively involve constructors and end-users of recirculating aquaculture systems to efficiently transfer scientific results into real-life practice throughout the project.

  • Scientifically describe parameter dependencies and validate process optimization possibilities



17 JANUARY 2022