Original ResearchPublished 21 July 2026Closing the loop in aquaponics: biological and physicochemical recovery of nutrients from aquaculture sludge for circular bioeconomyLuca Gerdes genannt Janßen · Mostafa Elshobary · Noémie Ramos · Tamara Schwenkler · Stephan Ende · Anja NokeFrontiers in Aquaculturedoi 10.3389/faquc.2026.1842840