Extracorporeal membrane oxygenation (ECMO) is increasingly being utilized for life-threatening cardiac and/or respiratory failure refractory to conventional treatment. Acute kidney injury (AKI) and fluid balance disorders commonly occur both before and during ECMO, with approximately half of cases receiving treatment with continuous renal replacement therapy (CRRT). Acute kidney injury, fluid balance disorders, and CRRT influence both short- and long-term outcomes in this population. The 36th Acute Disease Quality Initiative (ADQI) meeting was held in June 2025 to develop multidisciplinary international expert recommendations for AKI, fluid balance, and CRRT during ECMO across the age spectrum. This work encompassed five working groups: 1) epidemiology, risk factors, and outcomes of AKI and CRRT, 2) fluid management and outcomes, 3) indications for CRRT and fluid removal during ECMO, 4) best practices for performing CRRT during ECMO, and 5) biomarkers, extracorporeal blood purification, and drug pharmacokinetics and pharmacodynamics. As part of this work, knowledge gaps and research priorities were identified.