What was found
FUMES/SMOKE CAME OUT OF ECS VENTS IN THE COCKPIT AND CABIN AFTER TAKE OFF. FUMES/SMOKE MOSTLY DISSIPATED DURING LANDING. REMOVED AND REPLACED THE #1 AND #2 RECIRCULATION FAN FILTERS PER CRJ 900 AMM 21-22-12. PERFORMED OPERATIONAL CHECK PER AMM 21-22-10 AND PERFORMED LEAK TEST OF THE DUCT PER AMM 21-23-00. REMOVED AND REPLACED THE #1 RECIRC FAN IAW CRJ900 AMM 21-22-00. ALSO REMOVE AND REPLACED THE LAV AND GALLEY FAN IAW AMM 21-23-93. ALL OPS AND LEAK TEST GOOD.