Carmellia plays the position of a chaser, driver and winger in the 2023 Asian Canoe Polo Championships team. She was part of Singapore's U21 Women's team which competed at the 2016 World Championships (Italy) and 2017 Asian Championships (Malaysia). Carmellia progressed into the Senior Women's development team in 2018 where she improved on her technical skills before earning selection into the main team for the 2022 World Games.