The application of photovoltaic systems to aquaculture farms (hereinafter referred to as Aqua-PV) has been actively promoted by the Executive Yuan as an important means of accelerating Taiwan's energy transformation. While Aqua-PV in open fields is done using ground-mounted systems with a maximum of 40% ground-coverage ratio, indoor Aqua-PV is done using rooftop systems which permit a much higher PV coverage ratio of 80%. Although indoor Aqua-PV seems more profitable, indoor fish farming is more technologically demanding as it requires 24-hour water quality treatment. Because of this, solar developers need to bring in new teams or cooperate with bigger fish farming businesses to set up aquaculture systems. Yet solar developers and investors believe that indoor Aqua-PV projects are more easily controlled and a less risky business venture compared with outdoor projects where there is more necessity to deal with traditional fish farming practices and management styles. Therefore, although the cost per unit area of ​​indoor projects is much higher than that of outdoor projects, it is now the favored method. Last month, one project secured a massive syndicated loan totaling NTD$8.88 billion (USD$291.3 million) from several banks, setting a record for the highest amount ever provided for an Aqua-PV project in Taiwan. Compared with traditional aquaculture in open fields, indoor projects would permanently alter the land use and should be permitted only after special consideration. However, there is currently a lack of relevant environmental and social regulations and little to no management guidelines for indoor Aqua-PV. Without proper action now, large-scale development of indoor Aqua-PV projects will likely get out of control, resulting in serious environmental degradation and aquaculture problems.