Abstract:
This study assessed the current water quality management practices of medium-scale
ornamental fish farms in the Galle district, Sri Lanka, investigated the major barriers to effective
management and explored potential improvement strategies. Data were collected through a
structured questionnaire from 33 randomly selected farms registered under the National
Aquaculture Development Authority (NAQDA). Data were analyzed using Microsoft Excel (2021)
and the chi-square test. Results showed that 60.61% of the farms did not monitor water quality
on-site. Common water quality issues, including pH imbalances (54.90%) and low dissolved
oxygen levels (19.61%), directly impact fish health and mortality. For immediate water quality
improvement, partial water exchanges and enhanced aeration were employed. Long-term
strategies included regular monitoring, substrate siphoning, and bioremediation using aquatic
plants (Pandanus amaryllifolius, Eichhornia crassipes, Vallisneria, Pistia etc.) and natural water
conditioning using leaves (Terminalia catappa, T. arjuna, Musa paradisiaca). Most farmers
depended on traditional treatment methods, such as salt dips (43.08%) for managing fish
diseases. Notably, 93.94% of farms directly disposed wastewater into the environment without
treatment, raising concerns about environmental sustainability. A significant correlation was
observed between monthly income and on-site water quality measurement practices (p < 0.05).
The main barriers to effective water quality management were identified as a lack of resources
and high equipment costs. Ornamental fish farmers suggested that water quality management
practices could be improved through the adoption of advanced treatment technologies, access to
loans and enhanced support from government agencies and relevant institutions.
